Hi Blaze3456,
Ensure the audio balance isn't set to play from the right channel only in the accessibility settings on your Apple Watch. See how to check that here:
Accessibility audio settings on Apple Watch - Apple Support
"Change mono audio and balance settings
Open the Settings app on your Apple Watch, tap Accessibility, then, under Hearing, do any of the following
- Switch from stereo to mono audio: Turn on Mono Audio.
- Adjust the audio balance: Tap the L or R button below Mono Audio.
You can also open the Apple Watch app on your iPhone, tap My Watch, tap Accessibility, then turn on Mono Audio and adjust the audio balance."
If the issue continues, reach out to Apple Support for further assistance. You can use the following link to reach out: Contact - Official Apple Support
Kind regards.