Repeated data loss and data import not working

[EpsilonChurch]

• Chrome version: 84.0.4147.135
• Windows 10 Pro, Version 1909, OS build: 18363.1016
• 64bit
• KC3 Kai version: 34.8.1
• WWestore version

Occasionally, I find that my combat/pvp/expedition/etc history keeps getting cleared. I started exporting/importing my KC3Kai data, which worked at first. Tried doing it multiple times today and though it says the imports were successful, my history is still gone.