Don't bother with anything either of those two users wrote... My guess is they are either sig spamming... or very confused and didn't read the OP correctly.
One seems to be talking about ETH (and possibly ETC)... perhaps confusing Ethereum and Electrum, when you said you "moved your bitcoin account to Electrum" and believing you had converted your BTC to ETH/ETC
The other is just talking rubbish... These days, you cannot realistically mine your own BTC transactions... not unless you happen to own a massive mining pool/farm
Did you manage to get your balance all sorted? And is that error "unmatured" from an English version of Electrum or are you translating that from another language? I ask because I've only seen "unconfirmed" and "unverified"