Hello everybody,
I've been struggling with that for some days, so I came here to ask your help.
I have an Autonomous Database (type Transaction Processing) with an APEX instance free tier at OCI, and I'm needing to upload two certificates from a financial bank in order to use its REST API's. The bank demands mTLS. One certificate for a sandbox host connection and the other one for production host. (files .crt and .key)
At Postman I just had to add the certificate for the specific host as below, and everything works.

At Apex, as far as I understood, APEX_WEB_SERVICE.MAKE_REST_REQUEST will use the instance wallet (in my case file:/u02/app/oracle/wallets/apex_wallet )
I didn't find at OCI where I could run orapki command, use something like OWM (Oracle Wallet Manager) or something to add the certificates to the wallet.
I'm a little lost at the OCI universe, so I'll appreciate any help.