Hey! The team is aware of this bug, our engineers are working on a fix! :) Thanks for your patience!

Multiple similar reports recently - see https://schoolhouse.canny.io/bugs/p/completed-module-flagged-as-incomplete-when-i-have-completed-it-already. One user said to me that clicking Ctrl + Enter was the key for the submission to be recorded, but I don't know exactly when they clicked that. Normally just clicking the button at the end has worked but it apparently isn't working for a number of users.