Corporation Tax online Service - Cannot get Access

Hello, I have received my Activation Code for Corporation Tax. Now, the instructions to get access to the Corporation Tax online service are as follows: 1. Go to www.gov.uk/hmrconline 2. Select 'Sign in'. 3. Sign in using your HMRC sign in details 4. Select 'Activate for Coporation Tax' 5. Enter your Activation Code 6. Select 'Get access' The issue is with step 4. It's that on logging in to HMRC online using my government gateway details, there isn't anywhere on the screen an option to 'Select Activate for Corporation Tax'. On digging around, I found the option to add "a tax to my account". I clicked on that, and then clicked on "Corporation tax". Then, I filled in the details for my company, but I got an error with the following: "This information does not exist for Corporation Tax, or it has already been used to request access to this tax or scheme" Can anyone guide me to if anything has been missed?

Hi,
 

It may be that you have previously activated a business tax account using the corporation tax UTR and company number. Please contact OSH on: 0300 200 3600  Or get click Get help with this page. Thank you .