Can't set a sync key value for a record using the API

Hi,

Trying the integrate endpoint 

/integrate/<module>/:record_id/:sync_key_field_name/:sync_key_field_value

explained here,

I keep getting "error_message": "Could not find a route with 5 elements".

I can confirm that the record ID exists when I log in to the UI. the "name" field also exist in this record. 

Things I tried: 
 - Changing the version (v11_10 is not working at all)
 - Trying different modules with different records

The requested URL I'm using is:

PATCH/PUT https://{{base_url}}.demo.sugarcrm.com/rest/v10/integrate/Calls/{{record_id}}/name/Test

Can anyone spot what I'm doing wrong?