Error code 80151103 when I try to download my profile to my 360

Right, backtracking a little bit, I think I only created my 360 account in the last year or so, and only signed into xbox live quite recently. Everything around that time was working fine, no problems there. a couple of days ago I bought the 3 months of
gamepass ultimate for $1NZD, and after a headache and a half of the xbox app on pc telling me i didn't have it despite windows store eventually telling me I did have it, I wanted to use it for the xbox live features on my 360. Had a game of halo reach online,
worked fine, then a couple of days later I got the error code 8015190A saying "Your console can't connect to Xbox Live. Do you want to exit this session and test your network connection? If you are playing a game, you will lose any unsaved progress." after
trying literally everything, including chnaging my password, signing in on pc (which worked fine), adding 2 step verification and using a special code, removing 2 step, encountering a different code, 8015000A, and every other answer I could find online, I
ended up deleting the account off my xbox (without backing it up to usb, just didn't have one), clearing the cache and attempting to redownload it again. When doing this it gave me my latest error code in to add to my growing list of xbox error codes, 80151103.
As I'm writing this, the code has gone back to the code 8015190A, telling me that I can't logon with these credentials. I don't know if that's due to me randomly trying things like changing passwords, adding and removing my phone number etc. It still gives
me the Hi, VeryFrostyHam! (my gamertag) when I sign in to download my profile, then the loading bar just stops near the start, with the error following soon after. To sum up all of this seems to be related to me buying the $1 3 months of gmaepass ultimate
and the chaos that followed it, and I would really like to get this resolved, please don't tell me to clear my cache a million times, i've tried that.

:)