2nd Fire device. 1st one connected to public WIFI @work for 4 years. Then quit. WIFI turns itself on and off, repeatedly and rapidly. Won't stop doing that. Won't connect. Bought new replacement tablet. Same issue. Amazon "Support" staff have me do factory reset. Have done 5 of them. No change. Then, they say hospital's IT people have singled out my devices and blocked ME. IT people say 'Ridiculous! Don't know how, and wouldn't do it if they COULD.' All my coworkers connect their devices with no problems. My android personal mobile connects, no problem. My work mobile connects, no problem.
My conclusion: Fire tablets software mods are to blame, and the customer service people don't know enough to be any use at all. Am planning to return the brand new Fire able, and purchase an Apple tablet or other and NEVER own a Fire device again.