Drop index is not working

When I run
SELECT * FROM system:indexes WHERE name="indexName";
I get

“indexes”: {
“condition”: “(docType = “ABC”)”,
“datastore_id”: “”,
“id”: “bb6f23891470f893”,
“index_key”: [
“keyspace_id”: “id”,
“name”: “indexName”,
“namespace_id”: “default”,
“state”: “online”,
“using”: “gsi”

as result.
Now to drop this index I run DROP INDEX ‘indexName’ USING GSI; I get 3000 error.
I have no idea why this drop query is not working.

the statement is

DROP INDEX named_keyspace_ref.index_name 

so you should try this

DROP INDEX `id`.`indexName` USING GSI;