I own a small business have a UPS mailbox where I receive some of my checks for clients that wont pay online. This year, 4 of my checks(totaling 12k) were cashed(I received the check images from the customer when I was following up for the payment) without endorsement in a JPM chase bank account. I do not have a JPC account. I have asked the clients to cancel the check and issue me a new payment. One client came back today that their bank said they cant do anything and that I have to solve this with JPC. JPC says they cant disclose their client account details.

I have since asked all clients to either pay online or send a check to my office address. When the first check hit, I thought it was a simple mistake by UPS but now it seems more malicious

What are my options? Do I call the cops and meet them at the UPS store? Am a bit lost here of what my options are

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