I guess I don't understand how the station priority option works:

I have 2 request station and 2 supply station.

First req station require 38k copper ore and have priority 2.
https://i.imgur.com/MeoKnFa.jpg
Seccond req station require 100k copper ore and have priority 1.
https://i.imgur.com/iEmS8E9.jpg
First supply station have ~86k ores and priority 1.
https://i.imgur.com/AYHY8vr.jpg
Seccond supply station have ~3k ores and priority 0
https://i.imgur.com/bDufpg6.jpg.

So why i have information "low priority" if request station with priority 2 dont need ore at this moment and i have 86k ore in "magazine" on first supply station?

Hello. Thanks for the feedback.

Looks like a bad wording of the error.

You have about 5000 ore missing at the "W...k" request station, but you can't deliver it, because at the supply stations there is at least 4 wagons (8000 ore). This is reported by the staus "Small offer" (bad wording).

Until a station with a higher priority receives full supply, stations with a lower priority will receive nothing.

In your case, most likely other stations than "W...k" will never receive anything, because this station will always starve.

Best practice would be to set minimums at request stations, not supply stations. In my game, I set at the supply stations "minimum" equal to 1 element. And at the request stations, set the real minimum delivery (for example, 4 wagons).