Aetna POS II Plan Prescription Drug Benefits

Please forgive me for my ignorance. I’m extremely confused and could use some help.

I have Aetna POS II through a parent and have not used the pharmacy benefits until this month when my doctor sent a few medication prescriptions to CVS, which does take Aetna. At CVS I presented my health insurance card and was turned away by the pharmacist because it’s not an Rx card. Afterward I scoured through my Aetna online portal and the Aetna website trying to find the Rx card. I couldn’t find that Aetna’s even provides an Rx card or pharmacy benefits, so I called member services. The member service rep said that I do have benefits through a third party vendor called Optum Rx and transferred me to their representative. The Optum Rx representative asked me what prescriptions I had, then gave me the prices at CVS and Optum Rx’s home delivery service. Some were prices higher than CVS, some lower. I decided I was still interested with going ahead with CVS. I then called the pharmacy and they explained they still wouldn’t be able to fill the prescriptions without a BIN number, PCN number, and Rx Group number. I don’t know where to find these numbers. My parent said that they’ve presented the health insurance card at Walgreens to fill their prescriptions without any issues and never heard of Optum Rx.

Any help from fellow plan subscribers would be much appreciated!