email not working on iphone (works on PC)
I have an iphone 8+, I use the apple mail app and Telstra is my Telco and I have my main email ending in bigpond.net.au and my sub email ending in bigpond.com set up on it. About a week ago the bigpond.com account started saying cannot get mail in the mail app. In the end I deleted the account but now I cant add it back in, I get an error that SSL is not available, So I have tried to check my mail via safari app, chrome app and google app, edge app, firefox app for both bigpond.com and bigpond.net.au today and on all of them it says the page is not private, its not a private connection, connection untrusted and this is the https://signon.telstra.com.au/login
I can access the bigpond.com email via my laptop mail browser and various web browers but just not on my phone. Telstra believe it is an Apple issue, possibly due to 14.3 that I downloaded just before the issues occurred. Any ideas if there is a setting stopping this from happening so I can access the bigpond.com email again some how?
iPhone 8 Plus, iOS 14