-- Try dropping the constraint directly using the index name
-- Sometimes the constraint name is the same as the index name

-- Try these:
ALTER TABLE `bids` DROP CONSTRAINT `bids_inquiry_id_supplier_id`;
ALTER TABLE `bids` DROP INDEX `bids_inquiry_id_supplier_id`;

-- Or try with foreign key checks disabled:
SET FOREIGN_KEY_CHECKS = 0;
ALTER TABLE `bids` DROP INDEX `bids_inquiry_id_supplier_id`;
SET FOREIGN_KEY_CHECKS = 1;

-- If still not working, we need to see the full CREATE TABLE statement
-- to understand how the constraint is defined