fix: only call withdraw_collateral for non-zero amounts
@@ -511,7 +511,9 @@ impl<T: Config> RichVault<T> {
let to_release = backing_collateral
.checked_sub(&liquidated_collateral)
.ok_or(Error::<T>::ArithmeticUnderflow)?;
+ if !to_release.is_zero() {
self.force_withdraw_collateral(to_release)?;
+ }
// Copy all tokens to the liquidation vault
liquidation_vault.force_issue_tokens(self.data.issued_tokens)?;
