Need help for http request for a "Grünbeck" water softener

Hello.
As many of you seem to have made experience with integrating water softener data into openHab I was wonder if any of you came accross the issue with using the unit °dH (Grad deutscher Härte).

My setup (Grünbeck SD21) returns those values only in unit mol even though I’ve configured the item to use °dH.

Number:AmountOfSubstance   gruenbeckRawWater    "Wasserhärte Rohwasser [%.2f %unit%]"      {channel="mqtt:topic:MQTTMosquittoBridge:gruenbeckSoftliqSd21:rawWater", unit="°dH"}

I also get a corresponding warning in the log saying °dH is not a supported unit.

2024-07-08 11:28:33.129 [WARN ] [penhab.core.library.items.NumberItem] - Unit '°dH' could not be parsed to a known unit. Keeping old unit 'mol' for item 'gruenbeckRawWater'.

I’ve opened a separat topic on this problem:
Problem with unit °dH for item of type Number:AmountOfSubstance - using mol instead of °dH

Any help is highly appreciated.

Thanks and kind regards,
Ralph…