Weird barometer/elevation glitch

Epix pro sapphire titanium 15.76 screwed my altitude had to reset and restore last week. Mine did it last night at 02:58 went from 39m which is still wrong for my location to -2m then onto -6m when I looked at it around 06:30:this morning. When I started my commute activity it reset to 43m which is about right. On the garmin forum someone said to make sure that the altitude setting wasn’t set to baro only, I have it on auto at the moment. Wondering if I should set it to altimeter only.

Yes checked it again this morning same thing has happened. Recalibrated its self when I started my commute this morning. Seems to be a problem with the auto calibration that happens over night. Will see if I can switch that off