Is your Office TV Full HD 1080p and the stick was setup at 1080p and maybe the Bush TV is an older model HD Ready 720p which doesn't accept a 1080p signal ?
What i would try first is to factory reset the smart stick by holding down the reset button on the stick for about 10 seconds to see if the nowtv welcome picture appears on your Bush TV, then re enter all your WiFi and account details again on the stick.
Also if you are using an USB port for power on the stick from your Bush TV, then maybe try the supplied power adaptor instead to see if it makes any difference.
Hello, I am having the same issue! I had the same problem with my "Kenmark" tv, so I googled similar tv brand names and tried a few different ones and it eventually paired! I've tried doing the same with Bush but no luck so far. If anyone else could help it would be much appreciated.