InterFlora UK review: Very unreliable

Very unreliable, in my opinion.
Let aside the flowers price, about 3-4 times I usually pay when buying from other sources. But I wanted it done for next day so I paid .
Wednesday: paid and supposed to have the flowers delivered the next day, Thursday, in Central London. Easy, right?
Tursday: in the evening, they sent me a FALSE "confirmation " that it was delivered although it wasn't.
Surprised that I did not receive any sign from the person supposed to receive the flowers
Friday, after investigations I been told that the delivery person went to the location too late, after 06:00 PM (hout-of-hours), tried to dump the flowers on a desk in the reception lobby and when told it can't be left like this overnight, the delivery person left with the flowers.
Saturday evening: The days are passing and, after 3 days from ordering and paying, I still don't know if, when and how is going to be solved.
I would have expected Interflora to act straight away on the complain and to provide a way of addressing the situation in the same day.
It didn't happen.
Is it because I did not pay extra for faster delivery or for the annual membership?