Buyer stucks on last step while preparing an order

[KoalaSat]

Describe the bug When coordinator's confirmed liquidity is bellow the order amount, the buyer got stuck on the last step.

Reproduce** Steps to reproduce the behavior:

1. Your coordinator should have low confirmed on chain liquidity
2. Create and publish a SELL order with robot1 for an amount higher than coordinator's liquidity
3. Take the order with robot2
4. Block robot2's escrow
5. Robot2 should be moved to step 4 where they set the LN invoice (or onchain address) but it got an infinite loading instead

Expected behavior Robot2 should be able to go to the last step.

Additional context The back-end is returning 500 error because lndcli command is failing while trying to get either estimate_feeor wallet_balance, the back-end should expect and control it so the API can print a valid answer.