Shocking service

I placed an order with NetFlorist on 18 May 2020. I received repeated confirmation that order would be delivered on Sunday 24th - it was for a special occasion. Heard nothing from NetFlorist until I contacted them telephonically on Monday. I was told that they didn't deliver in that specific area on Sundays, so decided to deliver on Monday - after the occasion - and admitted that I should have be been informed so as to be given the option to cancel the order. They agreed to cancel the order then but I would be charged a 15% handling fee. This failure to deliver on the terms agreed was in no stretch of the imagination of my doing - why then should I be the one paying? Shocking service, especially during lock down when customers could do with a little boost on their special day. No phone back as promised – parcel delivered later that day – grrrrrr. Suppose they are happy as they have my money!