Issue salutation on contact details for invoice not updating

[Craig61]

When I update my contacts for a client, and then email the client with an invoice, the salutation ie Dear John Jones uses the original contact name when I first created the client record - there doesn't seem to be anywhere to update this record - can you help please

also if doesn't seem t be an option to untick the shipping address details and delete all entries so as to tidy up the invoice - I accidentally tick a contact