Just read the threads that are directly below yours on the front page of the forum 
For example this one Updating repository error or this one F-Droid: Error getting F-Droid index file => Unexpected end-of-input
Just read the threads that are directly below yours on the front page of the forum
For example this one Updating repository error or this one F-Droid: Error getting F-Droid index file => Unexpected end-of-input