R12.1.3 Upgrade - Error in IAS Cache: java.lang.NullPointerException while navigating to Supplier Si

Hello all,

We recently upgraded to R12.1.3 from 11.5.10.2 and since our upgrade, we are unable to navigate to the Supplier Site DFF form via Manage Sites - Descriptive Flexfields.

I have researched, but dont seem to hit a cause what could be causing this issue?

I see that the DFFs have been ported over (atleast the data is) into TCA tables and dont seem to have any corruptions. I am trying to query an existing vendor and thats when I encounter this error. I tried to disable the DFF segments - Title - vendor Sites and tried. Then the DFF screen opens up. I added one segment after the other, it all seem to work well, until I add the very last segment, that causes the error - Error in IAS Cache: java.lang.NullPointerException.