Missing fields in the index

Hi, We have dynatrace data onboarded into Splunk though API. we came across this situation. When I ran the search with an index (index=abc)for last 4 hours/24 hours. There are only few fields are displaying in search results where if I ran the search for last 7 days all fields are displaying. I selected All fields in the results too. There is no field limitation in limits.conf Can anyone please advise on this