There are legit bridges programs that fill in the "gap" between LPN and RN. Check if the programs are accredited, legit ones will tell you weather they are or not. I had an ADN, my bachelor's was in health administration, so when I completed my MSN through University of Phoenix I had to take 3 bridge classes to add the courses that were required for BSN. Best wishes!
Institutions that offer accelerated programs are a great way to transition from LPN to RN. Some even offer a bridge program to RN and/or BSN. Bridge programs are a bit tricky because if you are transferring credits from an different institution, they may not be directly applied/accepted for your bridge to RN or BSN.