There are two ways to tag your client with recurring work catergories.
1.To tag services with customers and users ----> Navigate to Workflow

Now click on the tagged customers number against the respective workcategory

After that check mark the respective client and select the resource user who needs to be tagged against the service. You can also mention client wise fees and cost.

2.Select Customers----->Customer Matrix
Place a checkbox against work category column against the customer name else
Download customer matrix and then Import the same file just by updating the excel. In this way you can tag multiple customer with the services.
After downloading the excel sheet just mention against the column for which the services needs to be tagged and import the same
"Kindly first create all the workcategories define their due dates after then tag the customers with services and resources. Then from the next start date the recurring task will generate automatically."