When you say that you bought them from a well known glasses store, I am guessing you mean a branch of a large chain.
If so, then go to a full service optician and ask them about repair.
I dont know where you are based, but I can recommend Thomas Carroll in Dundrum. They do repairs.
Maybe the glasses genuinely cant be repaired, but I would trust the advice of Thomas Carrolls or a similar optician over a large chain.
If you post where you live, someone else might be able to recommend an optician close to you.