While living full time I had a guest visit for several days.
I used the toilet right after her one morning. I found what looked like half a roll of toilet paper. And not RV paper. I nicely explained why we use as little paper as possible.
You guessed it. Next time I tried to dump it plugged. I tried everything I could think of including using a shop vacant trying to suck or blow it out. No joy. Called the septic pump company and they sent out a big pump truck. We tried sucking it out from one end and finally collapsed the black tank.
Then we bought a composting toilet.
I will never have to clean poo off of the bathroom counter ceiling again.....