Change the text of a Group

Hi. How to rename text “H1” to something else in a group?

Group gH1 "H1" <colorwheel> (gHH)
String gH1a1 "Name [%s]"	<colorwheel> (gH1)		{mqtt="<[mosquito...]"}
rule "MQTT 0674d2s change"
when Item gH1a1 received update
	var String SSS = gH1a1.toString //-> SSS = "gH1a1 (Type=StringItem, State=ROSA DHT11)"
	postUpdate(gH1.state as String, SSS)

does not work. Howto change?
2.option: if I could write to group as into String item (Group gH1 “H1 [%s]” (gHH))?
postUpdate(gH1, SSS) does not work.

You cannot change the text of a label for an item nor a group. You can change the state of an Item and it will change the part between the brackets. A group’s state is an aggregation of the states of all the members. See the Item wiki page for details. And even then, you will need to add an [%s] to the group’s label.

The problem with sendCommand and postUpdate sent to a group is that it also gets sent to all the group’s members, which I don’t think you want.