NIBE Heatpump / modbus binding issue

Hi, I’m using the NIBE heatpump binding which is based on the modbus connection to the heatpump, i.e. uses an Arduino or Raspberry to read out registers via RS485. I have successfully configured the binding and receive values from my heatpump in openHAB. However, all registers configured after the first one being larger than 1 byte never come through. In my example I have 8 registers with a length of 1 byte which show up in openHAB. The 9th register has 2 bytes (i.e. DegreeMinutes) and is shown properly as well. But the 10th register with 1 byte again never shows. Any idea??