I then adjusted the fee paid bar left to the max & its lower but still high saying - "the fee for this transaction seems unusually high 5.06%".
So that's basically 1sat/vB and the amount you're sending is about 300~500satoshi if there's only one input depending on the Electrum wallet type.
Perhaps you're mistaking mBTC as BTC unit? Check the unit shown in your balance.
If so, I'll just quote my recent post here:
Have you changed the default denomination from mBTC to BTC or using the default?
Because if you're sending in "mBTC" but intended to send an amount in "BTC", the actual amount would be as low as the transaction fee resulting with that warning message.
e.g. If you intend to send 0.01 BTC and typed "0.01" in the send tab's amount but the actual unit is in mBTC, you're actually sending "0.00001 BTC".
With that even a small fee of 400sats would be 40% of that amount.