So now things fix themselves? I've, since 1983, been an electronics tech, shop manager, training supervisor, systems tech, R&D engineer and Solutions engineer - never once have I found an electrical or electro-mechanical issue that "cleared up by itself". They appear to... at times... for a time.

And the battery has a date of purchase on the label that tells you how old it is. If it has no such label, time for a new battery.