Hello HomeDepotCustomer, We are sorry to hear that you were unable to use the S550e WASHLET. The WASHLET fits the majority of US toilets that feature a standard (non-proprietary) design. We provide a fit guide on the Home Depot page to help customers determine if the WASHLET will fit. We hope that you will give the WASHLET a try again in the future. If you need additional assistance, please reach out to us directly. Our Technical Support team is standing by to take your call. They can be reached at techsupport@toto.com or call 1-888-295-8134 between 8am - 8pm Mon - Fri EST and press 4 when prompted. We also have live chat on the TOTO USA website. I hope this helps and thank you for choosing TOTO.