'Duplicate' contacts being created with digits

Summary

OSVC integration

Content

Hi there.
My form has a field for email address which is is mapped to the primary contact for incidents through the native API integration with OSVC.

When the form is submitted, an incident is being created within OSVC (this part works). The thing is... even though the email address provided in the OPA interview is an exsisting contact within OSVC, it creates a new contact, similar to the exsisting one but with digits.

For example. There is a contact within OSVC with the primary email address: [email protected]
Submitted interview with email address [email protected] creates [email protected] in OSVC and on the next submit it will create [email protected] etc