Heart rate zones vs. power zones

I have been using ROUVY for about a month and I’m a bit confused about the relationship between power zones and heart rate zones. My FTP is 225. I have primarily been doing structured workouts and not just freely riding routs. When I ride in zone 2 power zones, my heart rate is in zone 3 or zone 4. For example, I just started the “Build your Endurance with Liv” workout plan and on the first workout, which is mostly Zone 2 power (for me 135-158 watts), my average heart rate was 148 which is zone 4. I tried to keep my heart rate down by taking deep breaths and just focusing on breathing but it had minimal effect. Is it normal to have your heart rate be that much higher?