Can't open Battle.net Mac - Another copy of battle.net error

I cannot open Battle.net on my iMac 2023 (M3). I get this error “Another copy of battle.net Setup is already running on this computer. Please close it and try again.”

I’ve redownloaded many times and did the Blizzard recommendations:

“1. Log in to the other user account, sign out, exit the Battle.net desktop app, and try again.
2. [Delete the Battle.net Tools folder]
3. Restart your computer to resolve problems caused by programs and services running in the background.”

All to no avail. Any suggestions? Please and thank you!

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