Hi, I've bought a copy of your source code. There are two major problems.
1. The music is muted. I do not know if you disabled it intentionally since you have announced there is copyright problem here.
2. The collision detecting have some serious problem. The bug is very hard to describe here only in text.
Since the engine have updated to 2.3 edition and force all legacy project to transform to adapt it. That may result in some serious problems. But I've seen the time-stamp of source code and project differs ( 2018 / 2020 ). Is that you have updated project but forgot the source code ?
Any reply will be appreciate.