Make sure you have a working backup of your data.
Your first option is to simply reinstall macOS from internet recovery (press cmd+option+R at startup) or an external (USB) drive.
Alternatively, this article describes the process of recreating the recovery partition.
Download a copy of the “Install OS X” or “Install Mac OS X” from the Mac App Store under the “Purchases” tab which matches the version of system software on your Mac (for example, the “Install OS X Mavericks” app, or “Install macOS Sierra” app)
Go to the developers website here and download the latest version of Recovery Partition Creator, it’s an AppleScript that will handle the recreation of the recovery drive
After the app has downloaded, right-click on “Recovery Partition Creator.app” and choose “Open” to bypass Gatekeeper
Follow the onscreen instructions, and select the primary drive you want to restore a recovery partition onto (typically Macintosh HD unless you named the drive differently, or are using a separate disk)
Make Recovery Partition on Mac
Point to the Mac OS X installer application you downloaded in the first step and let the AppleScript do it’s work
When the Recovery Partition Creator app is finished running, reboot the Mac and hold down Command+R to boot into Recovery and confirm the recovery partition now exists and works as intended