You may have encountered this kind of error message:

Why are you seeing this? This is because of the new OAuth policy of Teamwork that has recently been implemented. To resolve this, you and your team will have to re-authenticate with Teamwork.

Follow these steps to resolve this issue:

Step 1: Company owner will have to disable the company integration from this page.

Step 2: Disable the integration (if its not yet already) by clicking on the toggle button

Step 3: Wait 2-3 minutes and then re-enable the authentication again

Step 4: Enter your Teamwork username and password and click on Login

Step 5: You should have this message

Step 6: Ask all users to disable and re-enable their integration from this page