Bad powermeter calibration

Which PM do you use?

because your powermeter got wrong. 

Edge 530

Which Powermeter do you use?

Quarq PM spider 130 BCD

You may need to contact the manufacturer

Quarq Zero Offset Guidelines: 

The Zero Offset of a Quarq power meter does NOT have to be a certain number but should meet BOTH of the below criteria.

1. The zero offset value must return within +/-1000.
2. The zero offset must not drift more than +/-50 points during a single ride. 

Try to calibrate with the AXS app. If that gives you back such a bad offset value, then my 1st comment is 100% sure. it is common problem with Quarqs (that non-functioning, it has too high failure rate , comparing to other quality spider based powermeter brand/s/).