Two linked tables, with changing data on one table

Hi All.

I am trying to avoid a potentiel issue that might come with one of my reports.

The issue is this.

I have our costumers phone number on two different tables.

One is from an SQL Server, and another is in an Excel Sheet.

I need to link the SQL and excel sheet by the phone number. Easy enogh.

My issue is, how do i avoid this link to break on costumers who changes their phone number.

The number would automaticly change/update in the SQL table, but not in the excel sheet.

Any ideas, how i can avoid this break, without manually update the phone number on the Excel sheet every time?

Thank you in advance. :-)