Did you follow the directions I gave?
Let's try visual:
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As you can see, i have 3 jerseys -
the red and white original Nordeus one (you have green/grey)
black on blue custom design (you have red/red)
blue on grey custom design (you have red/white)

This is how you select which jerseys are used:
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As you can see, my custom designs have a check mark (they're being used)
my red/white Nordeus one has no check mark - it's not being used.

If that doesn't help you, then you are right - I don't understand. Sorry