It’s right, you know. In your rule, checkTemp is just a string.
There’s a number of problems here.
The Items you showed us are members of a Group named checkTemp.
It seems really unwise to re-use that name for something different within your rule.
The Items you showed us are members of a Group named checkTemp.
The rule you showed is triggered off a Group named gSolltemp , doesn’t seem to be a connection here.
As we said, within the rule checkTemp is just a string. To get hold of an Item by that name, so that you can in turn get it’s state, there are a couple of well-known methods shown in this post
But finally, commands sent to an Item will not immediately update its state, indeed may not update it at all.