My Sonos smart speaker has been playing up for a few weeks now, in that Alexa will answ...

My Sonos smart speaker has been playing up for a few weeks now, in that Alexa will answer questions but not commands. My daughter (she's ** and I'm **) has been over this week and she's tried everything she knows. She has two Sonos speakers and is convinced there is something wrong with mine, whereas I had been assuming I'm just not tech-aware enough to handle it. I bought the speaker in my local Argos (Holyhead) store on **nd January **** and obviously have all receipts. Would you kindly instruct as to how I might return it for exchange or refund? My daughter assures me that the manufacturer's guarantee should still be in place.