Converting a Dcount VBA to a Macro

I need to convert one of my forms from VBA on update event to a macro so that it is compatible with the web, but I am having problems with the dcount.

I need to on update check if the text and numbers entered into text box alaready exisits in a table works for the vba but not within the macro

Please find enclosed a snap shot of what I am trying to achieve

Thank you

Attached Images

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