The error in Cydia Impactor is a common assertion failure that occurs when the tool encounters an unexpected server-side issue or local configuration error while attempting to sign and install an IPA file.
Before 2019, you could use an Apple ID password to generate app-specific passwords easily. After Apple enforced 2FA for all developers, the process changed. While Cydia Impactor supported "App-Specific Passwords" for a while, Apple later revoked the ability for third-party tools to use these for device provisioning. The error code 200 often appears when Impactor sends a password (even a correct one) and Apple’s server responds with an authentication structure Impactor cannot parse. assert code 200 cydia impactor
Developed by the iOSGods community, Sideloadly is a direct competitor to Impactor. Decoding the "Assert Code 200" Error in Cydia
If the error is due to temporary server maintenance, waiting 24 hours often resolves the assertion. App-Specific Passwords: For users with 2FA enabled, you must generate an app-specific password Apple ID Management rather than using your primary password. Revoke Certificates: Xcode -> Revoke Certificates If the error is due to temporary server
Problems with your Apple ID or two-factor authentication. How to Fix Assert Code 200