typesense

Actually i need to support sorting for a field which is already in the schema ,
How can i update these fields to enable sorting ,
when i try to add sorting to a field which is already in schema i get this error
"message": "Field `field1` is already part of the schema: To change this field, drop it first before adding it back to the schema."

Method - PATCH
<https://domain/collections/testcollection>
payload
{
"fields": [
        {"name": "field1", "type": "auto","sort":"true"}
        ]
        }