No response from IRS

[jamsugan]

I have received a letter LTR12C from the IRS stating that your tax returns do not have the original signature. Sign and return the declaration at the end of this letter. I put my signature on that declaration form, and I submitted my response on IRS.gov/connect, where I created an account with ID.ME secure message. Submitted on April 20, but still no response from the IRS. How long will it take to get a response from the IRS? Thank you.