Group skill = Your whole guild skill level
Own skill = Your personal skill level
Your guild skill level is probably already beyond lvl 3 and therefore the bot doesn't need to upgrade anything. Set it to "own skill" and you should be good to go.
unfortunately I was happy too quickly
some accounts have been upgraded, some are still at level 0,
all accounts have the sane settings, all have got enough resources, no money saving
also if I used 1 hour city guard - upgrade doesn't work (so far)
what's the problem?