I'm not sure if OTC:GMGMF US follows just an exact exchange rate or what with GMG. I know that Canada:GMG trades at times when GMGMF does not, then there is the Australian ASX:GMG. Not sure how they correlate and reconcile on the chart. OTC:GMGMF closed today at $4.19 (+6.89%). No trading in extended hrs but showing 3.90 bid 4.43 ask currently.
Pull up your chart with OTC:GMGMF and see what the comparisons are.