Errors

Below is a table of the main error codes and checks that may occur during KYC procedures on the NVGlobal platform. For convenience, the table includes a concise description, a user-facing comment, and a brief explanation of the technology behind each check. The reference is aligned with the internal “Errors” section and example responses of /kyc/process and /kyc/session/status.

No.	Check Code	Description	User Comment	Technology Description
1	[general] bad image	The uploaded file is not an image	You uploaded a file that is not an image	The system validates the file type. Only JPEG and PNG formats are supported. If the file does not match these formats, an error is returned.
2	[general] too small image	The image is too small for proper recognition	The image resolution is too low; please upload a higher‑quality photo	The system checks the image resolution in pixels. If below the required threshold, an error is returned recommending a higher-quality upload.
3	[general] no documents on image	No documents detected on the image	Make sure you are photographing the required document	A neural network detector analyzes the image. If no objects resembling documents are found, an error is returned.
4	[general] not a selfie	No face detected outside the document	Clean the camera and try again, ensure the image is in focus	A face detector checks for a face outside the detected document area. If no face is found, the system requests a clearer image.
5	[general] low light	Insufficient lighting	Use better lighting or move to a brighter location	The system evaluates the illumination level. If below threshold, an error is returned.
6	[general] age requirement mismatch	Age does not meet requirements	Your age does not meet the requirements	A neural network estimates age with ±4 years accuracy. If it falls below the threshold or does not match the document-based age, an error is returned.
7	[general] black and white image	Black-and-white image	Do not use filters — the photo must be in color	The system analyzes color channels to detect grayscale or desaturated images.
8	[general] too many faces	Multiple faces detected on document image	Ensure only the document is in the frame	The system uses a face detector; if more than one face is found, an error is returned.
9	[document] unknown document type	Unknown document type	Ensure you are photographing the required document	The system classifies the document by visual features.
10	[document] bad document type	Incorrect document type	Ensure you are photographing the required document	The system identifies document type via a dedicated detector; mismatches trigger an error.
11	[document] too small image	Document is too small	Move the camera closer	The detector checks document size relative to frame; if too small, an error is returned.
12	[document] bad pages	Wrong document page(s)	Ensure you are photographing the required pages	Page classifiers verify correct side/spread of the document.
13	[document] no face	No face found on document	Ensure the portrait is visible	Face detector could not find a portrait zone on the document.
14	[document] text fields not visible	Fields not visible	Ensure the image is sharp and fields are not covered	OCR and segmentor detect field regions; if low visibility, an error is returned.
15	[document] bad mrz checksum	MRZ checksum error	Ensure the image is clear	OCR reads MRZ lines and validates checksums; mismatch triggers error.
16	[fraud] display or screen	Screen/monitor photo	A photo of a screen cannot be used; take a photo of the original document	Anti-fraud model detects moiré, subpixel patterns, and screen reflections.
17	[fraud] image edited	Image edited	Edited photos cannot be used	ML classifier detects signs of editing (inpainting, smoothing, metadata anomalies).
18	[fraud] image printed	Printed image	Do not use printed copies	Classifier detects paper texture and raster artifacts.
19	[face] bad face matching	Faces do not match	Make a selfie with the document clearly visible	The system compares document and selfie embeddings; low score triggers error.
20	[face] not all faces found	Not all faces detected	Ensure the image is clear	Liveness requires several images; missing detections trigger error.
21	[fraud] black list	Blacklist match	You did not pass the verification	Face embedding matches an internal watchlist.
22	[legal] legal proceeding existence	Legal proceedings found	You did not pass the verification	External database indicates open legal cases.
23	[legal] document not valid	Document invalid	Your document is invalid	Validation via structure, MRZ, dates, and external registries.
24	[system] balance too low	Insufficient balance	Top up your balance	Billing system reports insufficient funds.
25	[system] exception	Internal system error	Try again	Unhandled backend exception; session fails.
26	[document] bad quality	Poor document quality	Ensure the image is sharp and clean	Quality metrics: sharpness, noise, exposure, glare.
27	[general] too many tries	Too many attempts	You exceeded the allowed number of attempts	Anti-abuse limit on attempts.
28	[fraud] manipulation detected	Manipulation detected	Take the photo again	Aggregated anti-fraud score triggers rejection.
29	[fraud] document modified	Document modified	Document must not contain physical alterations	Detector identifies inserts, overlays, texture mismatches.
30	[fraud] logical mismatch	Logical mismatch	You did not pass verification	Decision Engine finds inconsistent dates, series, numbers.
31	[fraud] bad document photo	Bad document portrait	Do not cover the portrait	Portrait region shows occlusions or artifacts.
32	[fraud] mobile device	Mobile device screen photo	Do not use screen photos	Mobile-screen classifier detects subpixel and reflection patterns.
33	[fraud] document damaged	Document damaged	The document is damaged	Anti-fraud detects tears, wear, deformation.
34	[document] cropped	Document cropped	Document must be fully visible	Boundary detector identifies incomplete contour.
35	[document] no signature	Signature missing	No signature in the document	Signature zone segmentation detects absence of handwritten stroke.
36	[document] no stamp	Stamp missing	No stamp present	Stamp detector checks for circular/seal patterns.
37	[document] no required objects	Missing required elements	Required elements missing	Required fields: photo, signature, stamp, MRZ, etc.
38	[document] text field has low confidence	Low field confidence	Field recognized with low confidence	OCR marks field confidence as low.
39	[fraud] multiple documents	Multiple documents detected	Different documents detected within one session	Anti-fraud rule triggered by inconsistent document instances.
40	[document] expired	Document expired	Document validity period has ended	Validity date check via OCR/external DB.
41	[system] service timeout	Service timeout	The service did not respond in time	SLA timeout reached.
42	[document] other error	Other document error	Document does not meet requirements	Generic category for non-standard mismatches.
43	[face] is deepfake	Deepfake detected	Provide an original photo	Deepfake detection identifies GAN artifacts.
44	[face] is not alive	Liveness check failed	Provide a photo of a real, live person	Liveness engine detects absence of real presence (micro‑motions, series analysis).

Note: These codes are also returned inside the errors arrays of KYC API responses, which allows mapping them to specific processing steps.