This would happen if there are problems with the repository you’re passing. You should be able to find more information in a debug log file. See here for more info:
If that doesn’t help, you’d need to provide more details on the type of repository you’re using, what the code for instantiating ad passing it to LL looks like etc.
Hi Uzari, i think the community can better help you when you posting more details what are you doing, what are steps which version you use etc.
Otherwise you can try Jochen his information but with more details you will getting a better a faster solution 
try it out!
Debwin4 worked like a charm ! It showed me the exact error which was that I was missing a list and label repo table in my database.
That table was there in my local db but not on the production environment.
Creating that missing table resolved the issue !
Thanks a lot!