Blank landing page problem

[anon71]

When I try to access Hubs on my iPad, the landing page remains blank. No such problems on my laptop, which is running under Windows. I tried installing other browsers on my iPad (Firefox, Chrome, Edge)--same problem every time. I've come across mentions of this type of problem with iOS 10, where the advice was to update to iOS 11, but I've not managed to find anything in relation to iOS 12. My guess is that there would be something mentioned somewhere if this were a general issue, but I have no idea what else the problem could be or how to fix it, given that it seems to be independent of browser (or whether that browser has been used for anything else before). I cannot update to a more recent version of iOS to try whether that helps; iOS 12.5.3 is as up-to-date as my iPad (an iPad Air) can be. Any suggestions? Have I missed something obvious?