Diagnosis
The system is undershooting the setpoint. The primary cause is an incorrect "Heater Type" setting in the app, which affects the thermostat's power calculation and cycling behavior.
How to Fix It
Open the Mysa app. Select the problematic thermostat. Go to Settings > Heater Configuration > Heater Type. Confirm it is set correctly: "Baseboard (Convection)" for standard baseboards, "Fan Forced" for a fan heater insert.
If That Didn't Work
Check for external factors. Ensure the heater is not obstructed by furniture or curtains. The Mysa's temperature sensor is in the unit itself; ensure it is not in a direct draft or in a hot/cold spot on the wall.
Heads Up
The Mysa has a built-in temperature offset calibration feature. Use this only as a last resort after verifying the Heater Type and physical environment.