When tag in Firebase is a number I get thrown a "Error 1105, Unable to decode the JSON text"


When trying to read in some tag/ values from Firebase I got aError1105 message. After some investigation I found that the problem is the use of numbers as tags. Let me try to explain.
When my database has the folowing structure:
Then the folowing blocks do not generate any error and my listview gets filled

But the moment there is one number value in the tags, like:
then a push on the button3 generates an Error.
As you can see on the picture I tried with ‘120g’ as tag and that worked fine. Removing the ‘g’ so the tag becomes a number leads to the JSON decoder not being able anymore to decode.