My front derailleur will not stay in second or third it will shift all the way to the third gear but once I let go of my shifter it will spring back to first. So unless I hold the shifter on my handle bar in the proper position I cannot stay in second or third. Haven’t adjusted anything I just bought the bike off marketplace.
sounds like it could be a bad shifter, try to post pics of what you have
There are two kinds of people in the world, "Those who help themselves to people, and those who help people!"
If the shifter isn't clicking, then there's definitely something wrong with the mechanism inside the shifter.
Easy fix possibly though. Just buy a replacement and any local bike shop will slap it on for a bench fee.
If it was doing something like sticking, and not down shifting, that could be due to too much pretension on the cable or due to the spring being worn out in the front derailleur.