Find duplicate data in different column in a table

[Guest]

Hi

I have a customer database and would like to merge anyone who has the same
phone number or mobile number.

The table is
First name Last name Phone Mobile Email
John Smith 123
Mary Smith 456 123

So I want to find these Mr&Mrs Smith because John phone number is the same
as Mary's mobile

Can you help

 

[Guest]

Try these two queries --
angeline_1 ---
SELECT angeline.Phone
FROM angeline INNER JOIN angeline AS angeline_1 ON angeline.Phone =
angeline_1.Mobile;

SELECT angeline.[First name], angeline.[Last name], angeline.Phone,
angeline.Mobile, angeline.Email
FROM angeline, angeline_1
WHERE (((angeline.Phone)=[angeline_1].[Phone])) OR
(((angeline.Mobile)=[angeline_1].[Phone]))
ORDER BY angeline_1.Phone;