Several users in my office have the problem that we make our visualizations (they work perfectly) but when we want to save them we get an error. At first we thought it was a network problem, but then individually and on different networks we keep having the same problem.
Thank you for the post. It could still be a connection issue with the server itself. Is it possible that you check the Network log and Console (F12 → Network tab)? Click F12 right before the error shows up.
Please provide the following info:
What version of dhis2 is your instance?
Are you able to reproduce the issue in any of the play.dhis2.org instances?
Does this issue happen to a user with ALL authority or only some users?