How to cancel transaction?

Hello, so currently I'm stuck in the P2P Order list. The buyer was not replying and I've been checking my bank account to see if the payment has been sent. (good thing the confirmation receipt button is grayed out) and as I waited the countdown from 30 mins to go down (I was now at the last stretch of the minutes waiting for auto-cancel), the buyer suddenly became active and another 30minutes was added.

Is there a way to "cancel" this? Because I believe the buyer is a bot or on auto-buy mode. I'm actually warry too.

The "appeal" button is greyed out too.