Hello,
Thank you for contacting support.
You can’t add the rating option via the Service schema as that is not eligible for the rich result. These are the schemas that allow it: Product, Book, Recipe, Software Application, Course, Event, and Movie.
You may need to change the schema to the one that best fits your needs among the listed choices above. 
Here’s an article that walks through the process of selecting the rating option for a schema type: https://rankmath.com/kb/review-schema/
You may also refer to Google’s official documentation about it here: https://developers.google.com/search/docs/appearance/structured-data/review-snippet
Hope that helps and please do not hesitate to let us know if you need my assistance with anything else.
		
	 
	
	
	
	
 
			
															
					
					
					
						Hello,
						Since we did not hear back from you for 15 days, we are assuming that you found the solution. We are closing this support ticket.
						If you still need assistance or any other help, please feel free to open a new support ticket, and we will be more than happy to assist.
						Thank you.