Batteries no longer charge fully and 'charging faults'. Do I need to replace new battery?

[rdegraci2020]

I've noticed that the batteries, in my Ultra cameras, no longer charge up to 100%, but only top off at 92%

•  On one camera I keep getting a "charging fault" even though the camera is just sitting there at 87% charge and not plugged into power.
• Another camera, plugged into power, the battery icon will go from "charging" to "not charging" back and forth every few seconds and it won't charge higher than 92%.  It previously would say "charging fault" but no longer does so.

Does this mean it's time to replace the batteries with new batteries ?

Should I replace all of them at once or just the two out of the four ?

[jguerdat]

I'd start by removing and reinserting the batteries. You could even swap them between cameras to see what happens. Depending on results, use the Contact Support link at the bottom here for possible battery replacements, if within warranty. Maybe they would have suggestions if not.