Index Match function does not work with Textbox VBA

I have this code

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where

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Without 'SN' then it works fine, but because I want to index-match the value in Textbox1 I need to figure out how to use it.

I'm pretty sure the issue is something to do with the data variable type; i used Dim SN As Integer because its a number I want to use
But even with other variable types I'm finding errors like "Run-time error '1004': Unable to get the Match property of the WorksheetFunction class"

You need to match the data types.

Dimention SN as variant and add one line before that line

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