Not able to use SATA expander chip

Hey everyone

I recently built a custom PC with MSI B560M PRO-E motherboard which has 4 SATA ports and 1 NVME M.2 SSD port.

However, I have 6 hard drives and 1 SATA SSD which had to be attached to this system. So, my build was dependent on a SATA expander chip (Waveshare M.2 NGFF SATA to 5-Ch SATA3 Expander, JMB575 control chip).

The plan was to use 3 SATA ports on the motherboard for the SSD and 2 hard drives. The motherboard disables 4th SATA port when you attach something in the M.2 slot. Then I would attach the SATA expansion chip in the M.2 slot and connect the remaining drives to that chip.

I'm using the Corsair 450w power supply which supports 7 SATA connections and all the drives are plugged in.

Now, the problem I'm facing is that the motherboard data sheet clearly specifies that the motherboard supports SATA on M.2 slot. However, when I plug in the control chip with the hard drives, they are not getting detected. The BIOS clearly says that nothing is attached to the M.2 slot.

So, my question to the readers here is, how can I plug in all 7 drives to my system. Do I need a different M.2 control chip OR is there a way to split SATA connections so that I can plug in all the drives.

Thanking you all in advance