Hi @Pineapplecamper1, thanks for messaging the Community!
If there was an attempt to make a purchase using your payment details, then it’s possible they have access to the login details for your PayPal account, since Venmo is associated with them.
I’d recommend changing your login details to that service and to your email address just in case, and get in contact with PayPal for further assistance on this matter, since they should have more details on what happened.
Hope this helps to clarify matters!