charles.james, Ensure that the battery contacts are clean and install a new quality set of fully charged batteries and have charger tested or try another known good working compatible charger to rule it out as an issue. Reset clock and try camera. If problem persist, internal clock battery may be faulty or issue with bad components in camera. Pg D18, of the attached service manual below shows the internal clock battery and disassembly process to enable checking of internal wire connections/components/etc. for loose, damage, burnt. Good luck. I hope this helped you out, if so let me know by pressing the helpful button.
http://ss-it.de/data/servicemanuals/D50.pdf