cydhore on "[Plugin: Sliced Invoices - WordPress Invoice Plugin] Invoice and quote can't add a clients?"

Hello I Have downloaded and would like to use this plugin sliced invoices, but I have problem.
I can't add clients on either invoice or quote may you please help me to solve this issue it popup but it will not show me any fields to fill the client's info.

Thank You
Regards
Abdirahman

https://wordpress.org/plugins/sliced-invoices/