What's wrong with my iCloud?

I have been having issues with my iPhone 6 for a week now. It all started when i turned it off and on again to try and use LTE, and I was put through a reset menu where I had to put in my password, connect to Wi-Fi, and put in my Apple ID information, similar to what's done when you first get a phone. A few days later all my contacts are deleted. I turn my phone off and on and again I have to reset the phone. Then I have to confirm my iCloud in the settings to get my contacts back. A while later I realized all my pictures, messages, and notes that were in the iCloud were deleted. I've signed into iCloud numerous times after that, and only my notes have come back. Every time the phone was reset, I was logged out of most of my apps, and I have not been able to use some of them like Snapchat and Facebook. I also cannot take any pictures or videos or update my phone, because it says I have 0 bytes of storage even with no pictures or messages and deleted apps. Today I decided to see if anyone had the same problem, and I was told I should reset the whole phone. I clicked reset all settings, and now my phone does not work at all. When i hold down the power button, hold down the power button and the home button at the same time, the phone turns white with the apple in the middle and then it just goes black.