Redirect to admin-ajax.php

Hello,

Thanks in advance for the help. I have the plugin installed, but when I login, it redirects me to /admin-ajax.php

In the plugin settings panel, the redirect url option is blank.

This is what happens: https://vimeo.com/788477213/accb4b3dcc

Maybe this part is the mistake. But I don’t know how to fix it:

https://www.dropbox.com/s/6so47o8xoa5k8pb/boton-registro-booking.php?dl=0

Thanks.
Regards,

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