Apple does not sell modems. They sell routers, which are very different from modems. If you own a Mac, call Apple Care: 1-800-MY-APPLE or, use https://expresslane.apple.com/Getpr...TjSwBZX4gFstTz2dW2SZ552gd1QYLrx1Z!-1820874942Express Lane:
Doug
It may well be a router that the OP has issues with but Apple did make a USB Modem Apple Modem - Wikipedia, the free encyclopedia
Can't imagine there are many in use now though