I get many calls throughout the year about various calls my clients receive about their tax situations. First things first, calm down. Usually, actual correspondence with the IRS isn’t that bad. As long as you respond to their Letters or Notices with any additional information that they are requesting then all should be good.
The IRS will attempt to contact you multiple times via letter/or notice and the united states postal service. They will specify their reasoning and give you an opportunity to respond with your information.
https://www.stopfraudcolorado.gov/fraud-center/telemarketing-fraud/irs-tax-calls