Changed My Name it has a suffix but no one else has the name.

The suffix won't just vanish if the original tag gets freed up. Currently the policy is that accounts are closed which should free up the tag if the original owner does not sign into their Microsoft Account for 2 year. I don't know if that extends to banned
accounts as well. Late 2021 would be the earlist it would be freed up if that is the case.

Ah so they've added that back in there. The 5 year for gamertags started in 2016.

I read about names getting recycled if it becomes available will my suffix vanish if the name expires or do i need to change my name and then if it becomes available in the future change to it after that also it was my old account and i got it perma banned
for modding on dungeon defenders i was underage and did not know better. So do they recycle names to banned accounts also if the name gets recycled how will you know will you just be able to search for gamertags and it would not pop up anymore.

The suffix won't just vanish if the original tag gets freed up. Currently the policy is that accounts are closed which should free up the tag if the original owner does not sign into their Microsoft Account for 2 year. I don't know if that extends to banned
accounts as well. Late 2021 would be the earlist it would be freed up if that is the case.

they have tweeked the terms. just letting you know

You must sign into your Outlook.com inbox and your OneDrive (separately) at least once in a one-year period, otherwise we will close your Outlook.com inbox and your OneDrive for you. You must sign in
to the Xbox Services at least once in a five-year period to keep the gamertag associated with your Microsoft account. If we reasonably suspect that your Microsoft account is at risk of being used by a third party fraudulently (for example, as a result of an
account compromise), Microsoft may suspend your account until you can reclaim ownership. Based on the nature of the compromise, we may be required to disable access to some or all of Your Content. If you are having trouble accessing your Microsoft account,
please visit this website

The system doesn't see things like spaces as making a gamertag unique. So since there is an account with that same name, even though it has spaces, it is already in use.