How to forget (remove/delete) these saved O2 Wifi networks?

[idkwho]

Hi I am having a lot of trouble with trying to remove these four O2 Wifi networks from my Samsung Galaxy Tab S4 Tablet (WiFi only version). 

I have tried: Reset network settings and Factory data reset but these saved networks remain on my device.

There are four saved networks:

O2 Wifi

O2 Wifi. 1x

Wifi Extra 

Wifi+

The problem I have is that there is no forget button to remove these Wifi networks as can be seen in these screenshots:

[idkwho]

I Mistakenly accepted as solution.

Update: I went to a local Mcdonalds to connect to O2 Wifi but I still couldn't forget the network. Would flashing an updated stock rom be able to remove the saved networks?

[MI5]

I suspect the only way to get rid is if you root it.
Are they really causing you a problem?

[idkwho]

Yes I know I could just delete/modify the WifiConfigStore.xml file if I root it but I'd rather not because then I lose Knox.

I tried connecting my Galaxy S8 to O2 Wifi however it lets me forget it but I can't on my tablet. I added the tablet to a O2 Wifi account and then deleted but no change.

This is a problem for me because it auto-connects to O2 Wifi when I am out when near one and hops between that and BT OpenZone causing intermittent connections.