Bin collections/excess waste

Hi all. Sorry this is a bit of an embarrassing question, but I very recently moved to York and I've been having a little trouble with my bin collections.

I live in a house with three flats, and it seems we have a large purple wheelie bin for communal use. However, it's overflowing, and it hasn't been collected. I've noticed that on the rest of the street people either put out black bags or their normal black wheelie bin.

I'm assuming it isn't being collected because it's too much waste. I don't have a car so I can't take it a refuse centre. Does anyone have any advice on who to get in touch with?