Hello Eleni,
I have been doing some digging into my version of your issue and I think I may be on to something. Please check the business rules that are running on your form. I believe one of them may be the culprit as I have forms that were created before and after our last update and the older forms work just fine, but they are running far fewer business rules than the newly created forms are.
If the business rules/client scripts are not the issue there is one more thing I found that may be the culprit which is a bug that was mentioned in another thread. If you go to the configuration-->form layout add the variable "ignore price". After doing so look at your form and see if it is checked. It is a field that we by default cannot edit so there are two options to resolve the issue.
The first option is to remove the protections of this field and uncheck that item. After doing so immediately turn the read only option back on.
The 2nd option is to recreate the item.
This is caused by a bug that hasn't been prevalent enough to really get a lot of attention and is a bit hard to track down. Hope this is the root of your problem and you are able to get past it!
