Thank you for writing back with that information. Yes, we can resume with this tomorrow when you are back.
By blocked addresses, they are not the SAME as Junk email. In your Hotmail, you can block email addresses so that all emails coming from them will NOT reach your inbox, without notifying them. This is useful to protect you from spammers. They keep sending emails and the best way to deal with them is to block their email addresses so that their emails will not reach your Inbox any time.
So I suggest you check your Hotmail account first to see if you have blocked email addresses. If the @hotkey.net.au email is among them, remove it from the list.
To find your blocked emails, click on the small gear icon on the top right of the Hotmail page, then click on Options. Look at the left panel, under Junk email, click on Blocked Senders.
You also need to ask them to send a fresh email to you as test, that is, ask them to compose an email, then manually enter your email address to the TO field, type a simple test note, then send to you.
There is a difference when you are not getting their replies, and if you are not getting fresh emails from them.
Please let me know your results so that I can assist you further.