Toilet Won"t Hold Water

There is debris in the seal where the blade is.
Thetrford sells a bent screw driver to clean it.
I mad one out of a peice of wire. Wire is about the size of an old wire coat hanger. Start with a peice of wire about 15-18 inches long, bend one end at a 90 degree angle about one inch long. Make a handle on the other end so you can hang on to it so it doesn't drop into the tank accidentally.
Insert the short one inch into the groove where slide goes in. Gently move it circularlly around to clean out the groove.
It only takes a small peice of debris to let the water leak out. It could be even a peice of tissue.
Thetford Bent screwdriver

Actually, I prefer a Popsicle stick to a coat hanger to clean the seal.

Less likely to tear the seal.

All good advice and ideas from the above posters. I use a bush like this from Walmart (less than $2.00). It's soft enough that it won't harm the seal.

I put a bigger string on it and loop that around my wrist so that I don't drop it down into the tank..Works great.

there is nothing to scape or brush out,it is brand new

I sprayed a liberal dose of silicone spray on all moving parts and pivot points and it cured mine snaps back nice now and holds water.

Brand new!
Take it back there is something wrong with the unit!

Leaking toilets almost always need replacing to stop leaking. Other remedies are temporary at best.

There is a spring on the back side of the toilet that could be weak as you said or there could be other binding of the mechanism.. The only way to replace it is to take the toilet off the floor, replace the spring and flange seal, then bolt it back down. Ours is doing the same thing but I can lift the pedal with the top of my foot after flushing and the seal holds water. When we get back home from our current trip, I will replace the spring and flange seal, less than a half-hour job. The spring and flange seal are available from Amazon as a kit.

Yes - there is a spring in the foot pedal for the toilet. It if gets weak, the pedal will not raise back up enough to get a good seal. Yes - replace that spring.

Mine does the same thing.

I have to side step the pedal to let it snap shut in order for it to hold water. One day I'll try fixing it....