Do you have a choice to charge on and off the bike , try both. My charger flashes green until connected so possible connection issue??? Take charger cover off (unplugged ad sat for awhile to dissipate any left over charge) and look for a wire disconnected , scorched or burned. Speaking of burned do either the battery or charger smell burned? Anyway to test with another charger or battery to see where the problem follows?
That’s a cheap run of the mill 20$charger. You should have gotten a Luna or Grin and use the connector.
Nobody is charging at 2amps this days. My Bh/EM battery is a 12.6ah , can safely charge at 6.2amps.