Driver seat back is lying down on the back seat. Can't get it to stay in the upright position.

under seat will see lever latch pop it and seat will fold

When not using the compartment as storage, the read seats can be returned to the upright position as follows. 1. Pull both sides of the seat up into their upright position. 2. Pull down the seat cushion until it is returned to the original position. 3. Return the head restraints to their proper position. You can figure how to raise the Dodge Caravan rear seats by taking a look as to how they are lowered and locked: https://sherrychrysler.com/dodge-grand-caravan-how-to-fold-the-rear-seats/

For some vehicles such as the F-150, other adaptations are possible: https://www.builtrightind.com/blogs/built-x-design-blog/ford-f-150-secret-rear-seat-storage

Ok first you will have to take out that lever and remove the plastic cover to see if a. The pin on the seat broke -b.if the latch that locks the seat has broken -c. If the spring on it broke

Bad motor,, damaged switch, something jamming gear etc

There is something preventing the seat from latching in the upright position. Look for a piece of cloth or paper preventing the seat from becoming fully upright.

BROKEN ONE.U WILL NEED TO REPLACE THE BACK{UPPER SEAT}

You will need to do some testing with a test light, this problem could be a bad motor or bad connection and last a bad seat switch control, try to push button for the forward position while pushing in on switch button and maybe trying to wiggle a little.
I do not know what year,make or model this car is but try that first.

It may be fixable, the back will need disassmbly and maybe welded back together, then reassembled.

I just encountered this problem with my 2000 Ford Excursion. After fighting with it for several hours I realized that the section of the seat that is facing up towards the roof of the vehicle was applying pressure to the back of the seat that was facing down and preventing the back of the seat from coming up when I pulled the lever. So, the next time I pushed the seat up that is facing the roof while I pulled the lever and this resovled my problem.

There is a pin near the hinge that is supposed to catch and then latch your seat into an upright position. If this has come loose, simply engage it again and tighten it. If it is broken, you'll be looking to take to the shop and either get it wielded (not with the trouble and in some states reputable shops won't do it for crash test safety reasons) or have the seat replaced (the best and safest option).