We keep the jam for about a year. I boil the jars and pour the hot jam
into the hot jars. Then I usually screw on the lids which have been
boiled and are still hot. I usually do not use a boiling water bath. We
live in a moderate climate. And we store the jars at room temperature -
70 degrees +/-. I tried the wax this year,(which was the traditional
way my mother sealed this jam for many years), thinking that the pectin
or some other ingredient might be reacting with the suface of the lid.
These lids may not be the best type to use. They were purchased from
the bottling company at the same time I bought the bottles and I just
assumed they would be ok. They have a rubberiezd edge to give a tight
seal and the rest of the undersurface is a white finish on metal.

Do you know the reason why the USDA does not recommend wax for sealing?

Thanks for your help Edrena. Tunkey