You can call #227 to reach the billing department and see if you can restore your service. 

I can’t call anywhere, I don’t have service. Is there a way to contact online?

You can call that number even from a suspended line.

I am trying but it keeps telling me “Call failed”

So did Koodo suspend your line or cancel it altogether? If the latter, then I'm afraid that you lost your number...

Yes it was the latter, do I have to sign up for a new account/plan then? 

You can reach out to a Koodo rep and see if there is any way to get your number back. If it is recent, they may be able to restore your service on the same SIM card. Otherwise, you will need to sign up for a new plan.

Either schedule a callback on another line through Koodo Assist or send a message on Facebook Messenger or Twitter. https://Koo.do/Chat 

Thank you! The facebook messenger rep helped me get it up and running again.