Summer promotion and poor glasses

Went for an eye test on 28th of October 2025 and was given a prescription for reading glasses. Today went to fetch the glasses and enquired about the free pair of glasses. Was told it wasn't offered to me and therefor I now don't qualify for the free pair. The lady that phoned me had the audacity to say she can give me a quote, but I will have to pay for the glasses. I refused. She asked me to fit the glasses to see if it fits well. It fits perfectly. Upon getting home I tried to work with it on my computer. It is multifocal glasses and I understand there are different levels of focus on them. It is not in focus in the reading area at all and have only a small area which is focused when working on the computer., As soon as I move my eyes or head from this spot to read or work further on the screen the glasses are totally out of focus. I had multifocal glasses before and know that you should move your eyes and not your head. Not one of these methods work. I think after more than 10 years Specsavers have lost a client after spending a very large amount for these glasses.