I submitted my return for my business and after the fact realized I did not claim for a biz phone and monthly charge, do I need to create another return or wait til 2020
You'll need to wait until you receive your Notice of Assessment (NOA) from CRA and then you can either make an "adjustment" to your tax return or "ReFile" it.
Your NOA is usually received within two weeks. You can always log in to your CRA My Account and it will tell you when your NOA will be available to view, sometimes you might not receive it in the mail until later.
