First you have to make sure your OW Sapphire FF number is in the booking that is recorded on the BA system. Check that BA have confirmation about your status. Then you need to ring the BA call centre; preferably the UK London call centre.

The rule with BA calls where the answer is no is the put the phone down and call again, hoping to get a different agent. Some agents are just not very switched on. This is probably something weird in the booking that the agent is not picking up.

You say AA on BA metal. Can you be a bit more specific about which flight this is . It might be something to do with a certain flights.