As I see it, the instrument package that you have bought is completed by the essential software.
There is a functionality issue with the instrument, due to software issues. There's no separating them.
The instrument is within the warranty period and is 100% dependent on the software.
After three months, just the same as after a day, you are entitled to go back to the shop for a replacement or return from the supplier.
It is not the shop's fault, but your sale contract is with them.
Once the shop takes an item back, if they can't re-sell it, in a case like this, they have to take the issue up to get recompense from the manufacturer to cover their loss.
I personally feel really sorry for the stores who get caught in the middle when something like this happens.
They should never lose out due to a manufacturer's mistake.
Mooer have a recent product out there, probably still being sold, that ceases to work.
That is something that Mooer needs to sort out.