There should be an endorsement stamp on the back of the check somewhere, as all checks that go through a bank processing dept and get this endorsement. It may be faint and may not copy, but it should be there.
If what is reported as the back of the check is entirely blank, I betcha they only made a copy of the front of the check and not the back?
Also, these items can be retured and your bank should do so. 3-6 months sounds awful strange to me. You may be dealing with someone that needs some more knowledge and I would speak to someone in management about returning these items.
Lets us know how you make out.
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