Absolutely atrocious delivery service

I placed an order at the end of July, some items arrived 2 weeks later and others will be arriving, after several re-scheduled delivery dates, a month after I placed the order, incredibly slow in my opinion and given that I live in central London. I wanted to return some items from the first delivery but was told that I would only get a credit note in store. The only other option was to call Hermes, the delivery company, and arrange for them to collect the parcel but they are unable to specify a collection time so I have to waste 12 hours waiting at home for them. This is absolutely ridiculous when compared to the very efficient Collect+ or free Royal Mail returns labels that other companies use. Moreover, when I was trying to arrange for collection, all of the telephone numbers on the delivery note are no longer in use, adding to my frustration, and I have to return the whole delivery label with the returned items meaning that I have no receipt for my records in case an item I have kept turns out to be faulty. It is not possible to write reviews on the H&M website as far as I can see and I believe that this is because they offer such a poor service. I will never be using them again and would strongly advise against ever ordering anything online with H&M, it has been far more hassle than it was worth for what are essentially some cheap, poor quality clothes.