Ive been waiting 13 months for my marbel board (http://ridemarbel.com). They're ignoring all attempts to get refunds too. Time to try and get a chargeback and get one of these.
[1] https://twitter.com/RideMarbel/status/693081497264373760
[2] https://www.facebook.com/ridemarbel/videos/vb.75887281080344...
But no harm in asking your card issuer to see if they can help.