disk quota exceeded but there is space

I am getting 'disk quota exceeded' error but the partition is not full and user has unlimited quota. What is wrong and how can I fix it? xxx@mc:/tmp$ pyenv install 3.7.6 /home/xxx/.pyenv/plugins/python-build/bin/python-build: line 2048: cannot create temp file for here-document: Disk quota exceeded mkdir: cannot create directory ‘/tmp/python-build.20220629235336.143991’: Disk quota exceeded BUILD FAILED (Ubuntu 20.04 using python-build 20180424) Inspect or clean up the working tree at /tmp/python-build.20220629235336.143991 xxx@mc:/tmp$ df -h Filesystem Size Used Avail Use% Mounted on udev 445M 0 445M 0% /dev tmpfs 98M 1016K 97M 2% /run /dev/sda 19G 11G 7.5G 58% / tmpfs 489M 0 489M 0% /dev/shm tmpfs 5.0M 0 5.0M 0% /run/lock tmpfs 489M 0 489M 0% /sys/fs/cgroup /dev/sdc 4.8G 20M 4.7G 1% /baks tmpfs 98M 0 98M 0% /run/user/0 xxx@mc:/tmp$ quota -u Disk quotas for user xxx (uid 1000): none