Need help to identify limitations of NRF.setAdvertising

Hi
I am trying to do a smart power meter pulse counter with the puck.
It all kind of works, until the values get over a certain level. Then it throws all kind of errors and stops sending any data.
This is the setAdvertising code I use:

  NRF.setAdvertising([{
    0x2a03 : [String(power)], 
    0x2a04 : [String(pulseHour)],
    0x2a05 : [String(pulseDay)],
    0x180f : [Puck.getBatteryPercentage()]}],
    {interval: 600,
    name: "PM \xE2\x9A\xA1"} 
  );
  

All of the service data values are integers. Power is instantaneous power which can go to like 5000 and pulseHour and pulseDay can go well over 1000. I tried not using the string, but then it does not store the full value. Not sure where it breaks