Sync error: Master key is not loaded (desktop & iOS)

Operating system

macOS

Joplin version

3.2.13

Desktop version info

Joplin 3.2.13 (prod, darwin)

Sync target

Dropbox

Editor

Markdown Editor

What issue do you have?

Configured synchronization for Dropbox target, but am now seeing sync error stating master key is not loaded.

Settings --> Synchronization --> Encryption shows the following:

Encryption: Enabled
Public-private key pair: Generated
Master password: Valid

There is a single row shown in the Disabled Keys table. Attempts to enable the key result in a prompt, which states:
Your password is needed to decrypt some of your data. Please click on "Manage master password..." to proceed, or set the passwords in the "Encryption Keys" list below.

However, attempts to do either result in failures. If I attempt to manage the master password, when I save it shows the following error:
"Key 5c***b could not be reencrypted - this is most likely due to an incorrect password. Please try again. Error was: ccm: tag doesn't match"
And if I attempt to modify the password associated with the key, the 'Save' button has no resulting action.

Should the next series of steps be to disable encryption and then start over again?

Screenshots

So far, it seems that disabling encryption, synchronizing, then re-enabling encryption was a successful sequence in resolving the issue. A new encryption key was generated during this process. So far, so good.