@robb1334
You have two options but both start with contacting customer support. Verify your account and you can ask if they can suspend your account as lost/stolen.
You can then change your email so that you can verify your account and remove the 2FA verification from it in your account profile. This gives you access to your account back.
Or if you have a SIM card on hand or access to attain one quickly you can just do the Sim swap through the customer support agent. And put your sim card any phone in order to do the 2FA verification through the text message.
Do you have a backup phone you can use or will you have to buy a new phone. An easy and cheap option would be to look at the Alcatel smartphones that are on offer at public mobile. They are $79 come with a free SIM card and a $30 account credit. Subtract the credits and the phone will cost you $39. Usually phones are delivered within three business days from public mobile.
Just make sure that you order it using the email that your self-serve account has so either the new one you change it to or your old one. Although it will be in your best interest to use a new one now that your phone is stolen and your personal data is at risk. So changing your email and immediately ordering a phone from public mobile using the new email will get you a new phone and new SIM card within about 3 days.
Keep in mind your voicemail will remain active even if you're account is listed as lost stolen. You can access your voicemail by calling your own number and pressing star when it connects and entering your voicemail pin code.
