My watch keeps losing time and sometimes, it completely stops, it is only 3 years old. It wasn't long ago that I had a new battery installed but I took it to Wal-Mart yesterday, anyway and they said the battery has a full charge.

Try the battery first. Make sure to do the all reset inside of the watch after changing the battery. If it is not the battery send it to Casio. They may change out the complete module.

If your watch keeps time for a while, then stops and starts erratically, you most likely have one of several common problems.
1. You might have a bad battery. Sounds silly, but watch batteries have a limited shelf life, and if you installed a battery that's already been in a blister pack for a few years, the battery itself could be the problem.
2. Your "set stem" is not completely pushed in. Quartz watches are designed to stop ticking when the set stem is pulled out. They'll start up again when you push the stem completely in. There's a little finger or spring-loaded prong to keep the stem in or out. Sometimes, that little prong can break off from natural use. When that happens, the stem will work itself out enough to stop the watch from ticking. Natural movement on your hand will push it back in, and the movement will take off again. Check to see that you feel a firm "click" when you push the stem all the way in. Sometimes, when changing a battery, the movement will shift inside the case just enough that the stem doesn't quite catch in the locked, "full-in" position.
3. Your battery has a bad connection. Make sure that the positive and negative terminals of the battery are in good contact with the appropriate surfaces. I have used a tiny piece of aluminum foil at times to increase pressure on the watch battery so that it makes better contact.
4. Your watch movement has dirt in it that is jamming the gears. Modern quartz watches are amazing devices--a tiny amount of force from the pulse motor operates an intricate gear system that moves all the watch hands and day/date wheels. Even a tiny speck of dust in the wrong place on a gear can gum up the works and cause a watch to start and stop. Usually this will happen at set time intervals or at the same time every day, because that's when a particular gear tooth comes into play.
Closely related to this is an actual bent or broken gear tooth. Same symptoms.
A watchmaker can test the gear train by placing your watch in a special testing machine that spins the gears much faster than usual. If the watch hangs up from time to time, it's suggestive of problems in the gear train. Sadly, fixing the problem by cleaning the watch may cost more than replacing the entire watch.
These are the most common causes for this behavior. Hands that rub up against one another, or a defective quartz crystal are two other potential causes, but this should serve as a fairly good checklist for obvious problems.
Good luck!

If its a good watch, take it to a watchmaker. Dont know to find one 30 yrs ago they were inevery city

mcdevito75 here, One year old, most likely the factory Battery and at 1 year old the battery is old, who knows how long the battery was in the watch before you bought it 1 year ago?? The battery is the first suspect. Look for a small watch repair shop in your area for a new battery first.

Yeah, that's probably a battery that's about had it. eD

If you have had it for some time then it could be that it needs a clean.

I have seen manufacturers recommendations suggesting every two years for cleaning to maintain accuracy.

i think you may need to change the battery!

Some longines watch has built-in battery gauge. When battery is low, the second hand jumps every four seconds. If you have new battery installed and the problem persists then there is a short circuit somewhere that drinks a lot of battery juice.

I have a similar solar modle Ive had since 1995 , about 4 years ago it started loosing time and the second hand started double ticking. I sat it down out side on a cool summer day for the hole day in the bright sun and never have had a problem since. knock on wood! It was also runover by a car last year and still works good. I wont ever get ride of it. Hopefully this helps u guys out