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The code works fine with me. Therefore you should look at the way the workbook is shared. Are you uploading it to a shared platform or cloud? Is it being sent by email? Excel will normally open workbooks from strangers with code disabled. There will be a message bar at the top of the screen prompting the recipient to "enable editing" with caution. If your recipients don't enable editing the code remains dead.
There are more safeguards in MS Office and Windows installations which enable the user not to run VBA code by default, meaning the recipient may never be asked to "enable editing" if he has set his software to categorically not run code.
The best way to deal with the problem is to either be present while the recipient opens the workbook or stay on the phone with him during that process. You would need to know exactly, click by click, what is being done so that you can pinpoint the moment when your code is disabled.