Ok, To check the theme version go to WP ADmin - Apperance - Themes -and click on WPLMS, it will open a popup where you can see the current WPLMS version.
If your current theme version is 2.0.2 then skip the remaining part and clear browser cache and check if the issue is resolved.
You can share your Themeforest username and API key and we can check if you're getting the update.
Assuming that the auto-update is not working even after you;ve referred
this tip
You may have to manually update the theme, to update the theme all you need to do is download a fresh theme from Themeforest and follow the first part of this tutorial :
https://www.youtube.com/watch?v=hbcDjZVChIw
Make sure the file you upload is wplms.zip