Drag the EDQ Phone Validation component from the Custom – Managed dropdown (on the left) and drop into the Details standard component (middle box) or component of your choice.
Configure options on the right:
Click Back (Salesforce button).
If our EDQ components are used to validate a phone number or if the existing number in your database was entered manually with a plus sign (+), our component will display the plus sign (+) when your object is in view mode.
If you want to always retain the plus sign (+) when saving phone numbers, you must enable a config setting. This setting is called Enable phone code plus signs and can be enabled by following the instructions on our Configure global settings page.