Sorry if this is long. I have a 240gb ssd for os and 1tb hdd for media. I lost all data and now showing as a fusion drive virtual drive hfs . Drives were apfs. I tried trials of easeus and stella recovery software but found nothing. Dont have them backed up I know im an idiot but thats a different story. Im looking to see if there a way undo the fusion drive to make the internal drives separate and maybe then recovery software will be able to locate data.

Heres what happened:

Over the weekend I restarted my mac mini 2012 after it automatically install Catalina update to 10.15.4. After restarting it went to black screen and nothing more, I let it sit for hours. Power down and turn back on this time I got a white screen with apple logo and loaded to a screen that said something about an error during installation with option of shutdown restart view log and save log. I did restart and then it rebooted but stuck on black screen with apple logo no progess bar, again let it be for hours. I tried resetting pram, smc, and leaving unplugged for hours. I eventually tried to boot to recovery and it went to internet recovery mode. I opened disk utility and as soon as i did it said something about needing to repair drives before disk utility could read drives. I allowed ot to do that but stuck have way for hours. Powered down then got folder with question mark.

I used internet recovery mode to reinstall mac os to a usb drive, it was mountain lion original os for this mac mini. Once i got booted to usb and updated to El capitan i could see that my ssd and hdd were now show as a one fusion drive as virtual drive. If i use terminal diskutil list it shows the drives and partitions and the virtual disk. Disk utility i did repair disk and didnt help. Any help or guidance would be very helpful. Ive done alot of googling. I also have not written anything to drives or reformat or repartition since internet recovery mode.

Update: I updated to Catalina overnight on the bootable USB drive. Tried R-Studio by R-Tools and it was able to easily find my files and they are safely recovered on my backup network drive. Next step is for me to separate the drives and install Catalina on the SSD. And make sure i stay up on my back ups.