time machine share not working
Hi,
I've always used a USB Hard Disk for Time Machine on my iMac 21.5" 2017 without issues. Now I'm also using a MacBook Pro 13" 2017 and I wanted to use the same USB drive to do the backup, so I created a folder on the USB drive and set it up as a shared Time Machine destination. My Macbook can write and read on the destination, but when I select the drive on the Time Machine preferences it says that it doesn't support the required function. Any help? Both are with latest Catalina 10.15.6
iMac 21.5″ 4K, macOS 10.15