I have in SST a variable for stape_user and its working but there is one thing i dont understand and i can reproduce it.
After adding the user:_id with this variable in sgtm in user propertys there are no new hits on GA4 anymore (only some). I have to say that most users arent logged in so i dont know if that is important.
Is there to do anything or what i am doing wrong ?
Thank you agiain for your help
Adding a parameter to GA4 has no effect on the lack of hits. How did you determine that the hits were missing? Do you check the results in GA4?
As soon as i add the stape user id under user properties in the server tag and visit the site i cannot see the page views and so on in realtime data. when i delete user_id i immedeitely see the data in realtime, i can reproduce it 
Okay i got it 
There is something going on
I made a total new GA4 property with user_id, and as you said: It is working.
But then i went into GOogle Signals Settings in the new property and activated the 2nd part (its in german, see the screenshot)
As soon as i toggle that on, the property gets empty totally. all data is away immediely
That was or is the reason …
When you toggle it off the data isn-'T coming back again.
FIrst of all i want to say that it has nothing to do with stape.
Unfortunately i have seen this video to late where another one tells that your property gets medded up when using user-id
