Last Tuesday I tried to start a sim only deal online changing from my current provider Three Mobile to ID

i went through the process had the email saying it was being processed, then a while after i get an email saying i “ didn't meet the credit check criteria required for the contract you requested.”

I was surprised and rather stressed by this so rang and spoke to a rep, he tried to help me as much as possible and said that it was because of an unpaid debt from 2021 I was a customer then and told him my number from then and he said it was for a different number, i was really shocked and upset by this, and said i had no information emails or anything relating to the number he mentioned, btw the debt was for £8 only, i said i never fail to pay my bills and said if i offered to pay the small amount would it be resolved, this was complicated so he escalated the issue and put me through to someone in the credit/debt department and after a long conversation the representative assured me he was wiping this debt/clearing it ( even after I said I would pay the ridiculous amount even though they couldn't prove I had even owed it as the number and account and prior conversations that I have copies of relating to the actual number I had back then was a totally different telephone number from the one I was alleged to have not paid) he then told me to apply again after 24 hours

I will add i have serious health issues and am disabled and this has had a severe impact on my health.

so today I tried again filling out all of the details only to get the same reply

so...what actually is happening here, you say the ONLY reason I cannot have a sim deal is because of an alleged unpaid debt from years ago, that I offered to pay , but you (kindly)said you would wipe it clear, so i apply again only for you to say i have bad credit! 

I have NO credit issues, Three mobile never had any problems setting me up a credit deal for YEARS 

I have had NO other credit refused whatsoever from anyone.