We cannot do anything with a query like that. Fully document your hardware, what you did and what you saw. Feel free to answer in your native language if uncomfortable in English.
Somewhere in this systems BIOS Setup scenes, there should be a scene where you set the SATA Mode and, in the process, enable/disable RAID. In this scene or somewhere close to it, there should be a scene where you can see the Intel RST RAID configuration. You can use this scene to remove the two drives from the RAID1 array that you (inadvertently) set up. The SSD should be ok and still bootable afterwards, but the contents of the HDD will be gone (you will have to repartition and reformat).
Sorry I cannot describe this better; every manufacturer implements his BIOS scenes differently and I do not have a (well, modern) Acer laptop to look at..