Adding back old HD with data after initializing NAS with a spare old disk, due to failure to boot with the old one

[nrawert]

Hi,
After 3,5years of working ok, last month my NAS 253Be with only one HD in it (ironwolf 8tb in slot 1) was in a state of continous rattling but not completing boot. I recently realized that after beginning to boot from HD, lan lights stopped flashing. After I took out the hd, it booted to the internal setup OS where I updated to the latest firmware, and afterwards hotplugged the hd. The hd was recognised as previously initialized and I chose to restore it (not reinitialize it as it was the other option)- but it had no difference in the end result. After automatic reboot, no change - the device does't complete boot.
A have most of the important data backed up in my pc, but big files as 4k movies are not backed up elsewhere. Due to large size and no spare space in pc, retrieving those files through R-linux is not an option, especially when I need those files back on nas. I backed up only some smaller files I couldn't afford to lose in case of error.
I formatted a small (500GB) spare disk and used it to initialize my NAS as to see if it was something wrong with hardware. Put it in slot2. It booted properly and I created the first volume (thick). When I added the old HD (with the data) back in slot 1, it didn't prompt me to add it and to recognize file structure. When I added it manually, it gets recognized as storage pool 2 with system reserved space (140gb) and thick volume 6,8gb. I cannot see a way to access old filestructure on thick volume. (By the way the disk was ok when checking it with seatools)
Maybe I am missing something in the vast menus of options... Is there a way I can have access to the old filestructure;
Thank you for your time and patience.

[dolbyman]

data is accessed via shares..so if you want to access the files, create shares and point them manually to the old disk volume(s)

[nrawert]

Thanks, I haven't noticed that.