Likely related to the spring loaded contact in the plug end on the cord on the Jackery. Sometimes that metal tip gets a bit bound up for an easy clearance coming out of the hole in the plastic housing. I have had on occasion with some of those types of plugs needed to open up that plastic housing of the plug and use a needle file to slightly enlarge that opening so the tip can freely extend out all the way for making good electrical contact.
Other times the metal prongs on the sides are what quits making contact so I have needed to use needle nose pliers to tweak the bend to extend just a bit further outwards so it makes better contact.
The fixes are pretty simple. But if needed be aware you can buy a 15 amp rated new fused plug to replace the original. Hardware store, auto parts stores, Amazon item. I have replaced several of them over the years. Like most electrical connectors it has a positive terminal screw and negative inside the housing. Definitely a DIY job fix and not expensive either for this particular situation so no panic required. Plenty of YouTube videos to watch on doing a total replacement of that type of plug.