From great to poor service delivery

We bought a pair of hearing aids for my dad. Service was excellent at 1st, however now that this product which is less than a yr old(May 2021) has been giving hassles. Dad has taken it to them over 4 times and it's difficult to drive so far to the Musgrave branch for him where we bought it. Service has just deteriorated drastically. It has been two weeks with them and they have not even called once to update nor give any feedback. When we tried calling several times, the phone now just rings. This is not the service that we supposed to be catered for.