Help Trouble accessing some pages and PDFs using hotspot

[dwabbmkl]

I use wifi hotspot for internet connection on my laptop. Am unable to load select PDFs or access some secure pages (get stuck in a log in loop). PDFs and pages in question load fine when I use a different ISP, like at a coffee shop. While the hotspot on my wife's phone produces the same problem, using a similar phone at the US Cellular store worked fine. US Cellular tech support is stumped. I've scanned, eliminated or force stopped suspect apps, but no luck. Suggestions anyone?