Hi,
Unfortunately, a standard Companies House presenter account cannot be used for company formations on WeFile. To file company formations electronically, you will need to obtain a Companies House credit account (also known as a Companies House filing credit account).
A credit account is a separate arrangement with Companies House that allows you to submit incorporation documents electronically. You can apply for one directly through Companies House: https://www.gov.uk/government/publications/apply-for-a-companies-house-credit-account
Once you have your credit account credentials (Presenter ID and authentication code), you'll be able to use them in WeFile to submit your company formations.
If you need any further help, feel free to open a support ticket on your dashboard.