Restoring backup for iphone 6 from iTunes

Hi looking for anyone who could help with this...

My iPhone 6 was sluggish and screen had become unresponsive and there was ghost typing. I backed up my phone on my iTunes account and reset the phone. Now I am having issues in restoring the back up to my phone. I keep getting error messages on itunes. Can someone suggest a fix? I've lost all my apps and data :-(