so we need eth balance
finally the answer
............
The answer was in the link I posted as well:
But there is even an easier way to mint: send any amount of PoS to your own address (for example 1 PoS) and it would trigger the mint.
You can keep the gas limit at 200000 and set a gas price of 0.1 gwei (the lowest).
You would need to have some ETH for this, at least 0.000007 Ether.