It appears you have not taken the required minimum distribution from your IRA.

Why you received IRS Letter 5759C

1. You have a traditional individual retirement arrangement (IRA).
2. You are at least 70 ½ years old and the required minimum distribution (RMD) has not been taken.
3. The IRS sent Letter 5759C to notify you that IRS records show you have not taken the RMD from your IRA.

Notice deadline: If this notice arrives during the tax year in question, you have until December 31 to take the required minimum distribution (or until April 1 of next year if you turned 70 ½  this year and need to take your first required distribution).

If you miss the deadline: You may be subject to the 50% penalty.