Sorry to hear about this, sounds like the potentiometer in the wheel gave up.
If the unit is under warranty, you can reach out to your seller for warranty.
If it's out of warranty, you could either send it to our factory for repair or order just the replacement part and have it exchanged by a local service place.
Linsoul is our partner for replacement parts:
https://www.linsoul.com/blogs/announcements/shanling-audio-repair-services-at-linsoul-audio
Audiophonics is a good and reliable dealer. They ship almost everywhere and are quick to restock items. If anything is missing on their site, just send them email.