Fan Header not reading RPM on RIVE

[Blowitoutyouras]

So, I finished watercooled build last nite. Connected PWM pump to CPU 4pin header and all is well with that. Also, connected Bitspower flowmeter to monitor water flow to Chassis Fan #2 on the RIVE. NO RPM reading. Tested flowmeter to fan controller and I am able to monitor RPM reading. What am i missing here????? Thanks

[SUKARA]

What's model of you use the cpu cooling solution?
Did you have try to upgrade the motherboard latest verison bios for test it again?

[cx-ray]

Have you tried connecting a regular fan to the Chassis Fan #2 on your mobo? The header might be defective if it still doesn't read the RPM.