Canada ROE Web has a guide on how to create payroll extract files. As a premium software, you should have this functionality.

The flow should be as follows:
1. Users decide to create an ROE for a number of employees.
2. Employee data is reviewed and validated.
3. A Payroll Extract File is created.
4. Users upload and correct any incorrect information generated from the payroll extract file on the Canada ROE website before submitting.

https://www.canada.ca/en/employment-social-development/programs/ei/ei-list/ei-roe/user-requirements/appendix-d.html

Your API already uses XML, so this should be straight forward for the development team.

by: Ryan B. | 2 days ago | Payroll