OH3 changes JSON value

I’m getting from MQTT a valid JSON string. If I store this value in a string item, OH changes every : to a =. The problem now is that i cannot use the JSONPATH transformer to get out a the needed value.

For example: I am getting {“barometric_pressure_1”:974,“relative_humidity_1”:44,“temperature_1”:20} from MQTT and store it in a string item linked to my MQTT Channel. But now the shown value of the item is {barometric_pressure_1=974, relative_humidity_1=36, temperature_1=23} and I want to get the temperature value with JSONPATH but that doesn’t work obviously.

I hope you can help me

How do you know? i.e. where are you looking to inspect this Item state.
It sounds like an odd character set issue.

You know you can do that in the MQTT channel?

Are you using a generic topic Thing here, or have you created an event channel linked directly to your broker bridge Thing?

When you press on the linked item it shows it’s value.

Yeah I know, but i want to use one MQTT Channel for multiple data and sort out the data in the linked item itself.

Generic MQTT Thing

May we see your config? Will you show your events.log for a change to your Item?

A generic MQTT Thing suppots multiple channels, each of which can extract a different bit of JSON from the same payload, and update multiple Items of different types.