oracle on cloud (IAAS) as a source endpoint CONNECTION issue

[SaranyaK]

we are on qlik version 6.6, and we have an oracle source migrate to cloud (IAAS) recently. we are in the process of pointing this source to the oracle cloud. We used the connection string with TCPS with wallet info. The source connection suceeded but however when i start the task it just hangs (attached) .  Sometimes it completes with the below error.44Please advise what could be the issue.

Cannot connect to server ''(user '', Redo Thread 1, OCIthread 0)
Cannot attach OCI server
OCI error 'ORA-12560: TNS:protocol adapter error'

[Steve_Nguyen]

1. is the Oracle on the cloud or just as as service . if cloud :

https://help.qlik.com/en-US/replicate/November2021/Content/Replicate/Main/Oracle/oracle_cloud_prereq...

2. Does the connect test endpoint success ?

3. The error is about user connection issue. so best to set source_capture verbose ,, and re-run the task , and review the log to see any error before hand that could narrow down the issue .