Interesting, if the APs are managed by a ZD, you use your ZD's admin uid/pw. If they are in standalone mode, ie factory defaulted, use 'super' and 'sp-admin' for ISP priveledge access should work.
If you have a problem, does it work if you re-type the uid/pw? Does it work if you try to connect to the AP from a different browser (same uid/pw)?
If your laptop is having problem logging into a certain AP, does another laptop see similar login problems at that time?
If you both have HTTPS access problems, does the AP let you open an SSH session? (although only WebUI, not CLI, is officially supported)
If you cannot login thru the WebUI from 2 laptops trying multiple browsers, does it work for either one 15-20 minutes later?
If it's not working, while having a problem, if using a ZoneDirector, from Montitor/Access Points page, click the first icon to the right (blue/green = System Info),
and share the AP's support info file with Tech Support please.