No PAYE Activation Code received

Hello, hope someone can help. I registered for PAYE about 2 months ago and received my Employer PAYE reference around 10 days ago. I have not received any activation code though? Any idea how long it should take to arrive? This means I am unable to run my first payroll this month. Will this be a problem - do I send the information to HMRC a different way until I get a code? Or do I just wait and have them as late submissions? Thanks in advance.

Hi svickers,
Upon receiving your references, you then need to register for PAYE online by going to:
HM Revenue & Customs
select 'HMRC services: sign in or register' - select 'Sign in'
Then select 'Create sign in details.'
You will then be given a User ID on screen which you must take a note of.
You will receive an email providing your user ID (if an email was provided) and be asked to create your own password.
The activation code will then be sent through the post 7days after registering for Online services - sent to the business address.
You will not be able to send RTI submissions until your online account is activated. 
Thank you.