Unauthorized Transaction After Card Was Reported Lost

I lost my banking card and had it replaced. However, later in the same week, the original lost card was used to make unauthorized purchases. I was subsequently contacted by the bank, who informed me that they had noticed suspicious transactions on my account.

A ***** case was logged, but I have not received any feedback or resolution to date. I attempted to follow up telephonically, but was placed on hold for over two hours without any assistance by the guy called Tau, which led me to eventually end the call out of frustration.