How to change your Tumblr account settings
You may also change your blog’s name simply by removing the historical username and adding a new one. The secondary blog will take its place, as requested in Step 1. (1) To select Settings, tap on the Profile icon. (2) Go to the Settings page for the primary blog.
Click “Delete [your blog’s name]” at the bottom of the page. If it instead reads, “Delete everything,” you’re on your Primary blog; you can’t delete your Primary blog without deleting your entire account.
To start a new primary blog, log out of your current account at tumblr.com/register and create a new one with a different email address. You may not have two primary blogs linked to the same email address.
