Can anyone advise me re Klarna and default?

[Tickdurpin]

I received a notice of default for £85 around 6 weeks ago, the deadline being the day before payday. I rang them as soon as I was paid and they said sorry it's too late, you've defaulted.

I was given the details of the debt collection agency. However I've phoned them around 5 times over the last 5 weeks and they keep saying they have no record of me on file. Apparently sometimes it takes time to come through, but as I say it's been 5 weeks.

Anyway I phoned Klarna a few days ago and asked if I could just pay them. The advisor told me to pay on the app, which I did, and it now says £0 owed.
I have a default on my credit report which is not ideal.

Just wondering what to do in this situation, since I've now paid?

Have you checked your credit report to see if you actually have a default?

I have yes and it's on there sadly :(

There's nothing you can do unfortunately. If a default is on your credit file, it will be there for 6 years unfortunately.

I don't understand why my details never reached the collection agency and they've still allowed me to pay on the app? It's frustrating but what can I do.