mobile

I was connected to my mother's WiFi at her place and she has terribly slow Internet so I forgot her network to just stay in mobile data. 10 minutes later I got the authentication message for her WiFi, and 5 minutes later I was connected again. Checked my WiFi list and it shows it as an available network, but not connected. I have tried connecting with the wrong password, forgetting a couple more times, no matter what I do it still connects to her damn WiFi. What can I do (other than turn my WiFi off, obviously) to block this network?

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