What is wrong with my dog

Unless something is wrong with the feed dog, it should come back up as soon as you begin stitching again.

Many dogs love apples. Apples are great for dogs. The seeds contain the precursor to cyanide, which can develop into cyanide in the intestines, but your dog (or you) would have to eat lots of them to get sick and crunch up the seeds while chewing. Dogs, especially, are unlikely to chew the seeds, but to be on the safe side you can remove them before giving your dog any apple. Your dog might choke on the apple core, but most dogs will simply eat it like the rest of the apple. If you want to be safe, you can give your dog apple slices and throw away the core. Apple slices, without the seeds or the core, make a wonderful, healthy treat for dogs.
https://healthzex.com/nutrition/can-dogs-eat-apples/

Could be the feed dogs are lowered to do darning. Here's a manual:

PFAFF 294 Instruction Book Page 11

See if the A/B switch makes any difference in the feed dogs.

Sometimes these old machines haven't been oiled like they should and it's possible the feed dogs are stuck in the lowered position. Also, if it was used a lot the feed dogs get worn and no longer work like they should.

First, make sure the feed dogs are in the up position and NOT dropped for darning.

Second, check that the stitch length is set to at least a 2 or 2.5 to make sure the feed dogs will actually move the fabric a noticeable distance. The closer the stitch length is set to zero, the closer together the stitches will be until it will sew only in one place because the fabric will no longer advance.

The feed dogs need to move. They should actually rise, move toward the back of the machine, drop down, move forward to the position to again rise--this creates one stitch. If the fabric is not moving, then it is possible that your machine has not been cleaned and oiled recently. Old oil will dry and cause the moving parts to seize.

It was working now it seems to be frozen the needle part wont move


...

take a look in belts and gears where the noise comes
if broquen changed and put some wd40

Get her to a vet quick!

I just went thru the EXACT same thing, pulled up YouTube videos and discovered it was all about (1) how the LOOPER was threaded (the video taught me it is called "the puppy dogs head/ears" and that to thread it you follow the path of the ORANGE DOT (which often is combined with either blue/black, but just look for the ORANGE dot path no matter what the other color is with it) and that thread goes: "Around the puppy dog's neck and behind his ears". Honest to God this was part of my problem. (2) TENSION settings: I also discovered that even though the 936 has the adviser has all recommended settings for the stitches, you still NEED to tinker with the tensions. Specifically, I was set up for the WIDE COVERSTITCH to hem a knit skirt. I selected the KNIT MEDIUM (Auto M4) stitch and used these tensions: A needle 4, E needle 6, Looper was ok at 3. It worked like a charm and FINALLY I can do the stitch! Seriously, there are many YouTube videos (many lousy quality) that actually show and explain this stitch and how to set up your machine. Hope this helps!!! Good luck and happy sewing!

have you turned the handwheel at least 2 revolutions toward you after to put the feed dogs up?

The machine is old and may not have been maintained. The feed dogs may be rusted.

Remove the needle plate and bobbin. Lightly mist the feed dogs with wd-40. Wipe away the excess with cotton swabs.

Could it be that the feed dogs are down? I also have the 15358 and when I opened the bobbin area to clean it, I had this problem. Apparently, when you open the clips around the outside of the casing, it pushes the lever that adjusts the feed dogs to the right (lowering them). I didn't even realize it at first. Check your manual for adjusting this lever to raise the feed dogs. That might solve your problem.