Custom Folder Icons disappear after Restart

Dear Forum,

I have a NAS (TS-453 Pro, Version 4-4.2.1320) installed together with my iMac Catalina (10.15.5). On the QNAP I store a bunch of project folders, each with different custom folder icons. From these folders I created alias folders on my Macs desktop. Icons appear correctly until either Mac or QNAP reboot. All alias-folder icons disappear and show the default Mac OS folder icons.

Would it be possible to launch a script right after the reboot process and “refresh” or “synch” alias and original icons? Or may be there is a simple [set icon of folderAlias to icon of folderOriginal] script, which I could manually launch.

Thanks for your time.

Regards,
Ralf

Model: iMac 27" 2019, 10.15.5
AppleScript: 2.7 (Editor 2.11 (208)
Browser: Safari 605.1.15
Operating System: macOS 10.14