If you put <code> tags (not [code] tags) around your code, then it would be easier to see what you are trying to do.

I think the problem is with your use of the "param" function. I'm not sure how you think it works, but your usage looks like you're trying to set parameter values where I think you want to get them.

I think that you want to replace:

my $pay = $q->param(payment=>"discover","master","check");
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with:

my $pay = $q->param('payment');
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