Cannot connect wireless printer

My neighbour has recently changer her Virgin Media router and cannot connect her Kodak wireless printer. The printer is working but not in the wireless mode
Please help

Can anything else connect to the router, is it dual band and set to operate at 2.4ghz, have they tried setting it to another channel, done a hardware reset on the router? Anything else that's been tried? I presume the printer worked wirelessly immediately prior to changing the router?

Obviously she has checked the wireless key in her printer matches the one in her new router?