Closing personal dev account and removing phone number

how to remove the phone number for my personal dev/partner account so i can set up my work account with the same phone number. Currently get the following message after signing up with work account:

We can't continue with the signup process for the following reason:

• Your phone number is already associated with an existing developer account.

For help with your Microsoft account, go to Microsoft account and verify your information.

MS-CorrelationId: 00000000-41ab-48fd-8eb2-b22eb7025a9f

Code: 40901

steps taken:

• closed partner acc - personal
• removed phone number from microsoft acc - personal