I am next t sure but afair the ext3 home partition is created with a buffer of 10% free inodes. I say not sure but as soon as I saw the output it made 'click'.
You need to find directories where a lot of small files are stored. They do not fill up space but using inodes.
Please see e.g. here: https://scoutapm.com/blog/understanding-disk-inodes
https://stackoverflow.com/questions/...mber-of-inodes

did not see the other posts but still I think you ran out of inodes on /home. 10% free does not mean they are available.