Retailers can’t palm you off onto Sony, though I agree talking to Sony might be more productive unless the set has to go back as a near-DOA, when it does fall to the retailer to handle this. (And sort it out with Sony themselves no doubt, while you enjoy the replacement they must give you - you can refuse a repair attempt on something that has never worked).
The generic instruction for any Sony TV problem, though, is to do a Factory Reset, so try that now. This will save time when Sony ask you to do the exact same thing.
And may even fix the issue before you get there, though I am not holding my breath.
My favourite bedtime reading is a Sony product manual…
