Hi zubijaw - hope you're keeping well!
Can we suggest that you clear your browsers cache/cookies/history completely, then re-access the Dashboard?
All publishers were removed from Teachable coursework and moved into the Dashboard learning courses, a change that publishers have been notified of over the last month via the Dashboard (see screenshot).
You should now be able to proceed with coursework via the Dashboard with no need to login to a separate account 🙂.