I need to pay my prepaid bill but I can’t login!
Has the "month" on your service run out, and you didn't renew the plan before it expired? If so, you've been disconnected, as prepaid service cancels as soon as the plan expires. My Verizon access immediately gets revoked when this happens, which would explain why you can't login to the prepaid account.
You can contact Prepaid CS at 888-294-6804, hours: 8 AM - 7 PM CDT (Mon - Sat) 8 AM - 5 PM CDT (Sun) or visit a store to get set back up. They will have to give you a new prepaid account, but you should be able to get your number back so long as it hasn't been more than 45 days since you were disconnected.