Please call Highmark directly. The phone number is on the back of your health plan ID card. Highmark will help you with terminations or transfers of your HSA.
For terminations, Highmark will close the HSA and notify bank custodian to deactivate the account.
For transfers, Highmark will help you transfer your HSA funds to another vendor utilizing the bank custodian's transfer-out process or the new vendor's transfer-in form. An account-to-account transfer allows the balance to maintain its tax-advantaged status during the transfer.
Note: If you elect to receive the fund rather than having an account to account transfer, you will owe taxes and be subject to a 20% tax penalty for a non-HSA withdrawal.
You will have access to your account history via your Highmark login for the longer of 12 months or until your account no longer has a balance remaining.
For more details please refer to Terminating a Health Savings Account Through Highmark BCBS.