A meta description is a sentence that briefly summarizes what can be found on the page. Google may create different snippets based on search terms and page content, so the exact sentence you type may not always appear.
Distinguishing information on each page is more important than the number of characters or number of keyword repetitions. Describe the product's purpose, selection conditions, and actual scope of the service, and do not include unconfirmed performance figures. After making the change, view the CTR of related searches along with post-visit behavior.