Vent line pushed up..........toilet only flushes with dump valve open.......had to push stuff down into tank.
Sounds like......
Toilet drain line goes to far into tank
Folks are using too much TP and not enough water when flushing toilet (RV TOILET USE LESSONS NEEDED......water is your friend)
Vent line sticking above roof line (which was caused by improper venting initially)
You can mess with it........tank needs to be dropped/vent line---toilet line checked/corrected etc.
BUT I wouldn't. Way too much hassle.....covered underbelly/dirty tank/accessing top of tank where lines come in/2014 model.
Back to dealer and have them correct it.....and then show you that it functions properly before taking rig back.
Way too many problems for a new unit. ONE of which may be caused by folks not properly using toilet.......other problems are mfg. related