Still your router will give your hotspot an IP address,log into your router and find the hotspot and write the IP address down you may need it some day down the road it might save you an headache...........
I like the A-99 its a very good duty antenna, you also could check out the Tram 1499 its shorter and more easy to setup or the Sirio Thunder 27 all these antennas will work for CB radio.........
I have used the Little Wil before never had any problems it has a lower profile than the K40 ,the K40 has a longer whip/stinger than the Little Wil .......
Re do the sd card all over again and start over and make sure the other hotspot is off when you de the second one so your ATT hotspot can give it a new Ip address........