Mojave Reminders corrupted?

Mojave 10.14.6; Samsung external SSD

The Reminders app in NOT synched with iCloud. IOW, it exists solely on an external SSD from which I boot a 2015 iMac.

Symptoms:

•The Reminders calendar shows "September" but has the date configuration for October. Subsequent months are similarly off.

•The reminders I've created can be viewed in the various lists. But when I choose "Go to Today," it's empty.

•In the Reminders calendar, when I click on a particular day, it shows nothing even though scheduled reminders exist in the various lists for that day.

What I've done so far:

•Reset the SMC

•Zapped the PRAM

Neither has fixed it.

If the Reminders are corrupted, is there any fix?