Since jumble.social allows you to use more than one account and switch between them, I believe there is a bug in the "zap default comments" field, within the wallet/zaps settings tab. When you switch accounts, the information from the one you were using before overwrites, in that field, the information from the account you are using now.

nostr:npub1syjmjy0dp62dhccq3g97fr87tngvpvzey08llyt6ul58m2zqpzps9wf6wl