It works on my ipad when I use the web browser chrome app.
It works on my iphone when I use safari.
It also works on my pc when I use firefox.
What happens when you try to use Safari to sign in? What error do you get or what exactly happens. Also make sure your iPad is updated to the newest iOS, if it is out of date that could also cause an issue.
For now I would just suggest using Chrome or the built in Mail app on the iPad itself.
When I try to sign in to webmail, the webmail sign in page reloads with the same info filled in that I had originally typed in.
I've not updated the ipad IOS. Me & millions of others have stopped updating our devices because it's just slowing down operations.
Then that will be the issue, the longer you go without updating the less things will work on the device as they are optimized for the current versions. I would suggest, if you are not updating the device. To just use Chrome as you said it is working for you.
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