How to encourage buyers to rate the items?

Lets say some buyer is asking for support and you give support and solve the problem. And lastly, I say if you like the item or support plz rate the item. But nobody rates the item. They are happy with the support but dont want to rate the plugin. I know who bought the item and i can ask them to rate. Can anyone suggest me some best message to send to the buyers so that they will rate the item??

Always same problem , helped over 50+ customers to understand everything possible , but upon request or upon good support given , just recieved problem solved message , but no thanks , or no review for the item. all of them had their server issues to be solved so about item was 100% always clear and support was given to them to solve even their server problems. But hey , we cannot force them to review our item, that’s how it works for some. if they couldn’t get something that is not working for them and you cannot provide custom support for their custom work, you might get refund request or they can use that review left behind and give you a bad review out of it. And it is also said that , envato on the rate of 100% removes the bad review only 10% times. So basically , we cannot do much about it.