Prime Trust is our custodian, as well as the custodian of many other banking institutions and exchanges (including Strike, Binance, and Bittrex). So it is possible for a charge from Prime Trust LLC to show up on your bank account because of a charge from another service.
To determine whether a charge is from Swan Bitcoin or not, first, open up the individual charge and then look for the words "SWAN" in the code. If SWAN appears, then the charge was from Swan Bitcoin. If SWAN does not appear, then the charge is from another service that used Prime Trust.
If you are still confused who charged your account, you can contact support@primetrust.com with your unique code.