There were a total of 50 + 54 = <<50+54=104>>104 ice creams.
There were 50 x 3/5 = <<50*3/5=30>>30 chocolate-flavored ice creams sold.
There were 54 x 2/3 = <<54*2/3=36>>36 mango-flavored ice creams sold.
A total of 30 + 36 = <<30+36=66>>66 ice creams were sold.
So, 104 - 66 = <<104-66=38>>38 ice creams were not sold.
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