I installed GooLuck Wins on my previous phone but it was stolen. I got a new phone but I can't find the app on Play Store. Even after I signed into my Gmail account, the app is not still reflecting in my Play Store. I tried re-installing but it says 'item not found'. Please what do I do?
According to AppBrain, that app was unpublished from the Play Store on June 9, 2019, so that's why you are unable to find it in Play Store. Also, I couldn't find a trustworthy place to download its APK from, so can't recommend any non-Google app store.
In the future if you ever come across this situation again with any other app, do a Google search and visit appbrain.com links if they are listed in the search. This site is helpful to get status of an app available in the Play Store, including unpublished ones.