For newcomers to ask questions to the other users... this section will usually answer most questions... requesting resources (naq/UUs/ATs) is not to be done here...
Sounds like a bug to me, i haven't seen any mention of a limit on the amount of miners a player can get. I don't have too many myself, but the ones i train up every turn are increasing my income. I'll dbl check again next turn to make sure it goes up.
Working fine for me, i had banked before this turn kicked in so could see how much i got previous turn compared to how much next turn. It went up a bit from the UU's i produced, then i trained them to miners and it went up even more...