Impossible to find and/or request Self Exclusion, no one there willing to help

Hi, I recently opened a netbet account 2 days ago and was wagering beyond my means chasing losses. I got urges to keep gambling and knew I had to self exclude myself urgently as this is the only way I would stop. I searched on the netbet website and it said u can self exclude from clicking preferences under the deposit section so I went on there from my phone and there is no self exclude button. I only have a mobile iPhone not a laptop/computer. I therefore tried calling repeatedly the phone number provided by their website which is 020 3608 6024 and have taken screenshots to show how long I have been holding on for- up to 30mins 5 times now and still no answer just a recorded message saying operators are busy currently. I therefore sent a message filling out their email form online 2 days ago now and no response. In the meantime I kept getting urges late at night to gamble and try win back my losses resulting me in losing even more which I cannot afford. I then emailed and have sent 6 emails requesting to urgently be self excluded and no reply and I am still able to log in and bet. I then got in touch with their Twitter account @netbet making it clear I need to self exclude and they just said speak to live chat even though I made it clear I want to be urgently self excluded and begged them to call me so I can discuss & then they just said they will pass on the message. I've wagered way beyond my means and netbet have not acted swiftly or shown any compassion towards my problem. Please help. I am still able to log in and worried later tonight this will continue. It is sports betting.