Removal of the numeric discriminator from gamertag

I set up a new Xbox account a few months ago and when choosing my gamertag it put 4 digits after the name I have chosen. At the time, I gave it no heed as I thought that was normal for everyone, but then my friends joined and they had no such numbers in
their names. It got me wondering and I did a little digging and found out that the digits are only assigned to the gamertags that are already taken. Turns out the same gamertag was being used by one of my older Microsoft accounts which I no longer use. Nevertheless,
I recovered the account (cause the password was long lost) and changed the gamertag on that one to free it up for the Xbox account I currently use (it still had the free gamertag change from a while back). Now back to my current account: I cannot change to
the gamertag without the numeric discriminator I previously freed up because it's telling me it's the same gamertag =/

Eg: my current tag is "Alex#1234" and I want to change it to just "Alex", which I made sure to free up from my other account ("Alex" is not the actual gamertag I want to use). If I attempt to change it to "Alex" at https://social.xbox.com/changegamertag
I get the following message:

You already own that gamertag, if you’re happy with it you don’t need to make any changes.

One way around this would be to change my gamertag to something else and then again to the one I want, but that would imply me paying for a gamertag change twice while I just want the 4 digits at the end of my gamertag gone, and I made sure to free up the
original.

It's really just a nitpick, but considering how most games (on PC) don't support this new gamertag system properly (I have yet to play one), it really bugs me seeing those digits at the end of my gamertag in them.

Could anyone give some advice on how to best handle this?

:)