InsufficientBalance

The caller's spendable balance is below what the operation needs, whether a plain transfer, a crowdloan deposit or contribution, or a swap. Compare the account's free balance in System.Account (net of holds, freezes, and fees) against the amount being moved.

Declared by the Balances, Crowdloan, Swap pallets; it classifies to the semantic code insufficient_balance.

Remediation

Fund the signing account or reduce the amount; check with btcli wallet balance

The same explanation is available in the terminal: btcli explain InsufficientBalance.