Deductions & credits

I tried to go back and 0 my California Charitable Contribution on the Federal side, but for some reason it did not go through it says that I have already filed and cannot file again. I then re-added the contribution that I had just removed and tried to file again and got the same "Your transmission did not go through" message, I'm not sure what I am doing wrong, but I'll have to contact TT live again, hopefully they have a solution by now.