Here's some info. My pepper jelly, and especially my pepper jelly with apricots (lots of natural pectin in apricots) is always stiff. Depending on how I'm using it, sometimes I soften it in the microwave.

Here is a link that might be useful: NCHFP - stiff jelly

You can heat it before using or use as a meat glaze...but if you really want to "fix" it...you need to empty the jars and re cook with a bit more fruit. I think it's not worth that....just chalk it up as experience.

Linda C

Thanks for the info. I think I will do the microwave version of this fix up mess. I already re-made the jelly once to add more pectin and don't want to wash the jars again.
Ingrid