IC, the primary user should be user2 (nickname). I don't know why the primary user change it to user1.Ssh and delete from CLI. It's the primary default user and I wouldn't expect to be able to delete it but you might be able to disable it.
FYI, if you are using the AiCloud feature please ensure you have updated to the very latest firmware for your Asus router. The latest firmware has the security vulnerability updates to close the malware exploit in AiCLoud. More on the malware exploit in AiCloud here:Hey, did you ever solve this, @mickeyboy ?
I have the same issue - deleted all the other users, and I have one remaining which is NOT the default admin account.
I can't edit it (trying to change the password).
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