The prospects of fixing this issue are good, though it might take some investigation to figure out just exactly what's causing the problem.
[https://www.youtube.com/watch?v=mUg1_4noW2k|This guy] has some good advice. Lots of suggestions to try.
I will also say that there are several other questions with similar issues, with BLU phones specifically. As a BLU owner, I know my own phone can be janky sometimes. I once had my battery get stuck reading 11% for a whole day. I finally used it until it ran out of juice and then charged it nonstop back to 100%, and haven't had it happen again. This might be more complicated, though.
One of the questions ([post|195726]) has several suggestions as to why it's happening and how to fix it. Sometimes there's glue where it shouldn't be, or sometimes it's a matter of cleaning the port itself. Other times, it's from overcharging the battery.
Good luck!