Data that is entered on a page disappears when the user clicks save

We just upgraded to Financials 9.2 and our users are experiencing a intermittent problem. Since the AP module is our biggest module in terms of use, we are getting this problem reported the most in AP, although we also have had this problem reported in GL.

What is happening is the users will enter a voucher in AP, when they are done, click save, they get an error that a chartfield is required and they will notice that the Account chartfield is blank when they know they entered it, Sometimes, they enter the chartfield again, save and will get the same error again, the chartfield will be blank. Some users are also experiencing another similar issue when they save, they will get an error that INVOICE_ID or INVOICE_DATE is require and they can see on the page, there is a valid value in those fields, they