Recover Data from Raid 1 Disks

I used mdadm to create a raid 1 with 2 disks. After some time I reinstalled the OS (without wiping that 2 disks obviously). What I've done is to assemble that two drives with the following commands:

sudo mdadm --assemble --scan

sudo mdadm --assemble /dev/md0

sudo mount /dev/md0 /mnt/md0

Now if I type sudo mdadm --detail /dev/md0 it seems that everything works fine:

/dev/md0:
           Version : 1.2
     Creation Time : Sat Sep  4 11:16:49 2021
        Raid Level : raid1
        Array Size : 976629440 (931.39 GiB 1000.07 GB)
     Used Dev Size : 976629440 (931.39 GiB 1000.07 GB)
      Raid Devices : 2
     Total Devices : 2
       Persistence : Superblock is persistent

     Intent Bitmap : Internal

       Update Time : Sat Sep 25 10:00:06 2021
             State : clean 
    Active Devices : 2
   Working Devices : 2
    Failed Devices : 0
     Spare Devices : 0

Consistency Policy : bitmap

              Name : xxx:0  (local to host xxx)
              UUID : e7a0b95f:6fea0216:d094ee3f:2d73bf18
            Events : 6243

    Number   Major   Minor   RaidDevice State
       0       8       17        0      active sync   /dev/sdb1
       1       8       33        1      active sync   /dev/sdc1

But if I type ls /mnt/md0 there is just the lost+found file. How is it possible? Have I lost all my data? Is there a way I can recover them?