Airbnb query

[carhelpppppp]

I have a trip booked through Airbnb which was paid as a deposit, and the balance due in November (£550).

I have a random £250 I’d like to pay now but can’t figure how. If I select “pay now” it only allows me to pay the remaining balance in full.

can I not make ad-hoc payments?

Not to my knowledge, no. It is either deposit plus balance paid shortly before your stay or pay in full on booking.