I amended my 2018 taxes to deduct PMI premiums (tax law changed after I filed). I never received a new refund or any follow up. How do I follow up on this?

I received an email from Turbotax after I filed my taxes alerting me to a change in tax law which was made after the date I filed. This change meant PMI premiums were not tax deductible and I could amend my 2018 taxes. I followed the link and steps from this email to make the revisions. I have not received an additional refund nor any follow-up from Turbotax, IRS, etc.