hi @GoodVision
Error code 429 indicates “Too many requests”” error is an HTTP status code indicating a user or application has sent too many requests to a server within a given timeframe, resulting in temporary rate-limiting to prevent server overload.
To fix it, wait for the designated Retry-After time, implement exponential backoff, or check API/plugin limits.
How to find the wait time
Instead of guessing, you should check the HTTP response headers for a Retry-After value.
When you receive an HTTP 429 error from a server (or MCP), the waiting period is specified in the Retry-After header response of the error. Notice this in topic creator error log 
It clearly mentions when one can try again, when they encounter error code 429. So kindly check your error code log information you encountered and know when you can try again 
.
Also just to be sure when you try again, after knowing the Retry-After wait time, clear your cache and browsing history, and then login with id, and launch the assignment notebook from classroom page, just to make sure you are covered from every aspect when you try again.
Regards
DP