just get my stake again

Sorry is this has been answered before, what is the min coins that must be in the wallet for staking?
there shouldn't be a minimum, i'm a bit puzzled if it has been coded this way, and why (?)
stake is random for everyone but you should see your coins stake at some point within 30 days of arriving in your wallet.
So what i just dont understand, and again sorry for repeating a question asked before, why is my coins not maturing. Most of the transactions have 70+ confirmations
Are your wallet in sync , whats your block number now?
Does the wallet encrypted?If yes, have you unlock it?
When was the last deposit and withdrawal? in hours.