fill and sign saved signature gone

I use Adobe Acrobat. I typically just click the signature pen to get my saved signatures, but one day, they were gone. I verified I was signed in. It was just gone. I ended up making a snipping tool png copy from one of my other signed documents and used that as my signature. Then, next time I needed to sign, my original signature reappeared.  Now it is gone again.  This is a real hassel. It is extremely difficult to create a signature that looks real.  Why are my saved signatures disappearing?