Staging for Production: no staging needed?

Dear experts,

I'm facing very strange issue when trying the staging of material for production in EWM 9.2...

I get following PMA in EWM:

When I try to trigger the staging by using of /SCWM/STAGE, I get following message:

What could be a reason for such a warning? I tried to debugg the process and the systems even cannot determinate the materials to be stage...

I got following customizing in PSASTAGE:

I also mapped the doc types (ERP/EWM), the PSAs from ERP are transported and so on...so everything looks good to me.

Please could someone give any hint at least in which direction I have to look.

Thank you very much in advance

BR

Denis