Legitimate orders flagged

What steps can I take as a customer( not store owner), if Shopify keeps flagging legitimate transactions as fraud!? I’ve placed previous orders to same website to same delivery address from same ip using same credit cards before with no issues, no returns, but since I placed a high dollar transaction(which got canceled), any transaction now I do, is getting cancelled and flagged as fraud!! Is there anything that could be done? Is there a customer support email id that Shopify has?