Go to the Niantic website. Fill in your email address, subject line as “Delete account,” and provide your Pokémon name. To delete your account, check the four (yes, four) boxes. Remove the Pokémon Go app from your phone.
Log into your Pokémon Trainer Club account. Click Change Email Address. enter your current password, your new email address, and then Confirm your Email. Click Change to confirm the change.
Select the Settings option at the top right. Select the “Not Linked” option beneath Account next to the login provider you want to connect. Follow the on-screen instructions to link your account. You may use that login provider to sign in to your Pokémon GO account after your account is linked.
Go to your Google Account Data & Privacy page. Scroll down until you see “Your data & privacy options.” Delete your Google Account. Follow the steps to delete your account.
Visit the Niantic Kids Parent Portal and choose the “My Profile” option from the menu. Select the “Edit Profile” option at the bottom of the screen. Click the “Delete” button at the bottom of the page.