Can't connect to secure server

[AC Question]

I have two apps for work that I have been using for 2 years on my Samsung Galaxy Tablet and also on my Samsung phone. This past Wednesday, sometime between 6 pm and 8 am on Thursday something blocked my getting connected to these apps. Our IT department aid it was on my end; I am connected to internet, I connected on my device, then on a jetpack, then on a hotel to make sure it was not my connection. Thee page will not load, it says can't get data connection. I emptied the cache, cookies, I checked the time. I uninstalled and reinstalled and then I get a red box with a lock and two lines through he http part? I wiped my tablet back to factory settings and still cannot open these two apps. Any help?