Just want to put it out there that as an Aussie I have never ever ever heard ‘don’t worry about it’ used as a pay me back later. Usually it’s a ‘when you can’ ‘no rush’ type of thing. I’m with your friends on this one, you tell me not to worry about it I’ll take it as I don’t have to pay you back

and what did you learn ?

Uhm 'don't worry about it' DOES mean that you're paying and tell them to not worry about it... literally...

What? Whenever someone has said don’t worry about it one on one, in a group or frankly in any other context, it has always meant I’m paying for you and don’t worry about paying me back, as in, it’s on me. If it’s that much money apparently being accumulated in debt, why weren’t you clearer in the first place?

Apologize. You told them you were paying. When you saw the bill, your terms changed. Find a way to pay the money and stop picking up the tab. Maybe after an apology, you will find they may help you with the debt or start picking up your tab to help out. And maybe learn slang better before using it in a social setting so this doesn’t happen again.

"Don't worry about it" has always meant the person saying it means no need to pay me back as I have it covered.

There are no Aussies who think “don’t worry about it” means “pay it slowly.” Perhaps you are an immigrant and have gotten the wrong idea of the slang? I’d explain to your friends that you didn’t know and maybe they’ll pick up the tab next time but they def don’t have to pay you back. If your debt is what you say it is, why have you been rushing to the bill? (Unless you’re Asian, we all know it’s a fight to death on who gets the honour of paying the bill!)

this is coming from an Australian. No it doesn't.

Um. No we don’t. When we say don’t worry about it, we mean don’t worry about it, if we want you to pay it back, we say shit like, you owe me.

Say what you mean rather than choosing to say it in such a way that implies oh o don’t know, not to worry about it. *******.