Monitor is too pink - deep red color gone.

[Rubricen]

How can I calibrate my monitor.
After using my laptop with an external monitor for a couple of days but picture suddenly became a little pink on both displays.
I disconnected it and run laptop as standalone now.
Another laptop is used for same external monitor with no problem. Monitor is okay.
It does not affect white or other colors but red has became pink and deep red color is gone.

Where to start?
Diagnostic software from HP is run. No fail there. 

[Jupitero]

Hello.

It is important to determine whether this is a hardware of software problem.

If the HP boot logo, BIOS screens or the UEFI diagnostics show the pinkiness as well, then likely your laptop graphics board is faulty. (UEFI diagnostics can be invoked at computer boot up menu by hitting ESC, then F2)

Try also booting into Safe Mode in Windows to exclude the possibility of graphics drivers (or other software) from changing colors. Check that the Windows Night Light is disabled. Your laptop graphics driver (Intel/AMD/NVidia) probably has its own control panel where color hues, contrast and such can be configured. Try resetting them as well.