Please help: ORA-29273: HTTP request failed ORA-29276: transfer timeout

We are running 12.1.0.2 OEE

We are Getting intermittent Ora error while executing a rest call from SP

[Error] Execution (124: 1): ORA-29273: HTTP request failed

ORA-29276: transfer timeout

ORA-06512: at "SYS.UTL_HTTP", line 1258

ORA-06512: at "EDB.GET_EXPECTED_VALUES_914", line 57

ORA-06512: at line 12

What we tried:

We changed default timeout to:

 UTL_HTTP.SET_TRANSFER_TIMEOUT(896000);

It worked for sometime and now we started getting this time_our error again.

The time_out occurs in 1.5 minute that means it does not respect the parameter in UTL_HTTP.SET_TRANSFER_TIMEOUT(896000).

Any help will be appreciated