Rakuten Kobo Downloaded My E-Book With the Wrong File Extension

I use Rakuten Kobo, operated by Dr. Firm, to download and read e-books on my phone. However, I experienced a problem with a book I purchased. Even though I paid for the book, the file was downloaded with an incorrect file extension and could not be opened. When I tried to report the issue through the support center, the system gave me an error and would not even allow me to submit a support request.
Because of this, I contacted customer service. They reviewed the issue but were unable to resolve it, and I have not received any follow-up for approximately three weeks. During this time, I downloaded another book, but it had a similar problem. Once again, the system gave me an error when I tried to report the issue. As a customer, having to go through additional steps just to report a problem and then receiving no response is extremely frustrating and undermines my trust in the service.
I request that Rakuten Kobo's management be made aware of this issue and that the software and support teams urgently resolve both the incorrect file extension and file-opening problem and the technical issue with the error-reporting system. I want to be able to properly read the books I paid for, which cost approximately $4 in total, and have the inconvenience I experienced resolved. Otherwise, I would consider completely stopping my e-book purchases from the service.
