Connect IQ MPA and Power data field

If I understand correct , once I install the data field and put in my fitness sig code the values on my garmin should reflect my MPA ? My current MPA is 889W but the Garmin data field always shows 1200W . Am I missing a step ? I’m using the trial subscription .

Resolved: I had to remove it using the desktop Garmin Express app , then re-added it using the desktop app, all is correct now.