if clear data from buzz app will delete only servers. nothing will happen to your other apps. if you reset your box the you will loose your apps. since you are having issue with buzz tv app only thats why I recommend clear data from buzz tv app only. hope this will help.
hmmm try to clear cache and reboot and see if that helps. try to clear data as well if possible. you will loose server info...etc If you clear data. do it on your own risk. write down portal and credentials...etc before clear data. make a back up of server if you want to.
some providers dont care about anything. some lock with your ip, your isp, device id, geo location..etc. I like the one locks with your info so not easy for people to steal.
because you playing channel from all categories. try to play one channel from your favorite list other than thats current playing then try and you will see it will stay in your favorites.
what color light do you see on front of the box? does color change when you press power button on remote control? try to remove hdmi cable on both ends and insert again. try a different hdmi port if available and try a different hdmi cable if possible. if nothing works then factory reset box from AV hole using toothpick.
some iptv provider let you customize package and some dont. so if you have access to panel and allowed to remove unnecessary categories then you can remove if not then contact your provider and ask them to remove what you wanted to be removed.
just clear cache only.
more channels with lots of guide info will increase data. thats why its better to custom package if you dont watch channels brings lots of info. so multiple servers will increase a lot more.