Removing items from a different artist
DSPs (like Spotify, Apple Music, etc) will sometimes group artist profiles together if they share the same/similar artist name. So if your profile is mixed up with another artists on a DSP, Supertape ends up importing some items that aren't yours.
So having another artist's music show up in your inventory can happen for a few reasons.
You share an artist profile with another artist on a DSP.
Another artist's release was added to your artist profile on a DSP.
We're syncing the wrong artist profile.
Contact your distributor
The best way to deal with this issue is to contact your distributor (Like Distrokid, CD Baby, etc) to see if they can help clean up your profile on various platforms so that you're the only artist who can release music to it. This is a common problem so most distributors will have a help article to point you in the right direction.
Re-syncing the correct profile
If for some reason Supertape is syncing the wrong artist profile, you can always Delete the platform with the wrong profile from the Platforms area, and then add the platform again with the correct one.
You can also simply hide an item that's been imported that you don't want to show up on your website.