There is nothing wrong from what I can see.
Something is obviously wrong.
You sent ETH. It confirmed. So you are all good. If you want to withdraw, simply go to withdraw, put in your wallet address and entire Liqui balance. Then withdraw. You will get your ETH back minus transaction fee.
You probably missed part of OP where he said he didn't receive ETH in his account, so how can he withdraw it?
If you still don't see it reflected in your account balance, contact support.
Which OP did
What the warning means is don't send less than 0.1 ETH and don't use a smart contract. Just use a normal send. Did you use a normal spend and from what wallet?
Answer from support doesn't make any sense to me either.