AITA for selling my friend’s concert ticket after her payment deadline passed?

In February, I bought four concert tickets the moment they went on sale. My friends paid me within a week except for Leah, who asked whether she could wait until the end of the month. I said yes.

The end of the month passed. Leah told me an unexpected car repair had wiped out her extra money, so I gave her another six weeks. I was not struggling to pay my credit card, but the ticket was $180 and I did not want to carry it indefinitely.

We eventually agreed on a final date: May 15. I wrote, “If I do not have the money by then, I’m going to sell it.” Leah replied with a thumbs-up.

On May 15, nothing arrived. The next morning I listed the ticket at face value. A buyer paid within an hour.

That afternoon Leah sent me $100 and said she would send the remaining $80 on payday. I returned the money and told her the ticket was gone.

She was devastated. She said she had not understood that I would sell it the morning after the deadline without one last message. From her perspective, sending more than half showed that she was finally solving the problem. From mine, she sent partial payment only after four extensions and after the date we both called final.

The other two friends are now in an awkward position. Leah says they should refuse to go because attending without her rewards me for being rigid. They say they still want to attend but asked whether I could contact the buyer and offer to repurchase the ticket at a higher price.

I tried. The buyer declined.

Leah then found a resale ticket in another section for $265. She asked me to pay the $85 difference because a warning on the morning of May 16 would have prevented all of this. I refused.

I know deadlines should mean something. I also know I had already waited three months, so another six hours and one text would not have harmed me. Part of me sold quickly because I was tired of being the patient one and wanted the uncertainty finished.

Leah has not accused me of stealing or lying. She says I behaved like a ticket company instead of a friend. I think friendship was the reason she received months of flexibility in the first place.

AITA for selling it without a final reminder and refusing to cover the new price difference?