CSRF verification failed

I get the error CSRF verification failed on specific mems in a course. I have tried doing all kinds of things with my browser settings. I get the error across all browsers. I tried it on my phone and got the same error. I can still review items just fine, but when I try to learn the new mems this error pops up and won’t let me continue.

I tried getting through the level by just dismissing the error messages and clicking to stay on the page. That worked, but it was really annoying. Then when I finished the session it gave me the error again on the grade screen. This time it did not give me the option to stay on the screen. It sent me back to the home screen. It didn’t save any of my progress. So I just can’t complete the last 2 levels of a course.