This is an accepted solution.
Karlie here from the Shopify Support Team! Good question! There are a few different ways to help you verify what your past banking information is - I'll list them below.
If you still can't find your past banking information and you're looking to update your account within your Shopify Admin - then let me know here. We can take this conversation to email and I can escalate this up to our accounts team for you.
I hope this has answered your question. If not, or if you have any further questions please let me know. I will be happy to help!