mine was refused on sep11..maybe was more overconfident as having schenegan,u.k. and u.s (with stamp in 2017 for 10days -valid thru 2027),and invitation letter from my son (he is on study visa since almost an year)
Strange .... you have very good travel history + USA VISA and travel history entitle you for CAN+ category...
What is your reason for refusal and what documents you attached ?