Lack of speed and distance basically means it hasn’t got a GPS lock. As it needs gps positioning to calculate those items. I presume you didn’t have it set to an indoor profile, which would switch off the GPS element?
I've always had good service from Garmin. My 530 broke within warranty and it was replaced. I didn't seem to have a problem contacting them.
And the 530 issue might have been down to someone dropping it.
It has a silicon case now.