I noticed it stop vibrating yesterday and Its always on vibrate . now I miss my texts and phone calls .
Go to Settings > Sound, check if you find vibration settings here. If you find it, enable it and see if vibration works now. If it still not, try installing this vibration testing app I found in Google Play: VR Mobile (link). If after testing and it doesn't vibrate, then it's a hardware issue you need to address to a phone technician.