You have a few options to redesign/change your logo:

To Redesign and download the logo from the website:
  1. Log in to your account from MY ACCOUNT
  2. Click on ORDERS
  3. Click on order number # 
  4. Click on EDIT
  5. Design your Logo and click > SAVE DESIGN
  6. Navigate to your account and download your Logo

2. Change the logo using HD Editable logo files:

If you have HD editable files (AI + EPS + PSD), you can change the logo yourself with illustrator/photoshop. Here is some useful information from our blog: How to Change Your Logo Design With Illustrator?

You can buy the HD editable files  AI + EPS + PSD  that you can change the logo yourself with illustrator/photoshop. Click here

3. To Let the graphic designer change your logo:

You can buy one round of modification service from the design studio and the designer will correct the logo and resend all the logo files to you ASAP. Click here