NFL Network

I don't understand why I lost the NFL Network last year.  You say I can upgrade my package but I don't want to spend alot of extra money just to get one channel I want especially when it was in my package at one point.  You say it has something to do with contracts and money but how am I watching it for free on my cell phone?  And how is Sling TV able to have it along with many other channels for $25 a month?  I call bull on your excuses and I'll be switching back to Sling in 2020.