Using graylog6.0 panos 11 and upgraded to graylog 6.1.1 issue after upgrade

Hello Team,
I had graylog 6.0 receiving paloalto panos 11 logs, sure missing some fields not indexed.
I read about the date in the **graylog 6.1.1 and it supposed to have better indexing of panos11, which is my case.
I upgraded my server but now my graylog 6.1.1 receives the logs but almost no indexing “very few fields”.
why that? is this by design? am not a developer, so how to read the logs fields now?
TIA so much.