Domain/~domain/about in url after pointing nameserver to web hosting server

Silverstripe Version: 3.6.6

I tested a website via IP address and ~domain. Why is there still the tilde (~) folowing the domain name?

I tested a website on live server via IP/~domain and now that I point the domain nameserver to this I still have the ~domain following the domain name: domain.com/~domain/about.

The home page is fine with only domain.com/ showing.

I tried to do a domain.com/dev/build?flush=1, but that didn’t change anything.

Has anybody any idea why this is happening and what to do about it?

Thank you very much.