Forum registration activation issue

I placed an order for axbb-e package and waiting for it to be delivered in a couple of days. I have been trying to register at this forum but am not getting registration activation email. I have tired a couple of different email addresses that I normally use. I have sent a few emails to cncdrive guys about this issue. I specifically mentioned in my emails that I have checked Spam folder but in response to my email they keep telling me to check Spam folder. I am not sure if they read my emails in full which are not very long.
This time I created a temporary GMail account and tried to use it to register. I did get activation email straight away. My original email address is "outlook.com.au" and that's what I want to use. I am not sure if the forum system has any issue with outlook.com.au addresses. I had similar problem a few years ago where the system was omitting .au from email address and emails were not reaching to me.
Could the administrator look into this issue please? I do not want to use GMail.
This time I created a temporary GMail account and tried to use it to register. I did get activation email straight away. My original email address is "outlook.com.au" and that's what I want to use. I am not sure if the forum system has any issue with outlook.com.au addresses. I had similar problem a few years ago where the system was omitting .au from email address and emails were not reaching to me.
Could the administrator look into this issue please? I do not want to use GMail.