My surface isn't charging when plugged in

My surface doesn't charged when plugged in the charging cable, but I'm not sure what the problem is. It could be my surface as the cable is plugged in correctly, but it could also be the charging cable itself as sometimes when it's plugged in the light at the top of the cable flickers and turns off.

Either way my surface hasn't charged for a while - it's now shut down because of lack of battery power and I don't have another charger.

Any ideas on how to help? Thanks in advance :)