No space left on device - Centos 7

Trying to restart crontab service and getting no space left on device, however there are plenty of space in the server. Any help appreciated.

[root@at-app-dev-01 backup]# service crond restart
Redirecting to /bin/systemctl restart crond.service
Error: No space left on device

[root@at-app-dev-01 backup]# df -i
Filesystem       Inodes  IUsed    IFree IUse% Mounted on
devtmpfs         995120    311   994809    1% /dev
tmpfs           1001102      1  1001101    1% /dev/shm
tmpfs           1001102    423  1000679    1% /run
tmpfs           1001102     16  1001086    1% /sys/fs/cgroup
/dev/vda1      83885504 568778 83316726    1% /
tmpfs           1001102      1  1001101    1% /run/user/0
[root@at-app-dev-01 backup]# 

[root@at-app-dev-01 backup]# df -H
Filesystem      Size  Used Avail Use% Mounted on
devtmpfs        4.1G     0  4.1G   0% /dev
tmpfs           4.2G     0  4.2G   0% /dev/shm
tmpfs           4.2G  404M  3.7G  10% /run
tmpfs           4.2G     0  4.2G   0% /sys/fs/cgroup
/dev/vda1       172G  8.9G  163G   6% /
tmpfs           821M     0  821M   0% /run/user/0

[root@at-app-dev-01 backup]# stat /tmp
  File: '/tmp'
  Size: 93        	Blocks: 0          IO Block: 4096   directory
Device: fd01h/64769d	Inode: 4194379     Links: 7
Access: (1777/drwxrwxrwt)  Uid: (    0/    root)   Gid: (    0/    root)
Access: 2020-02-09 21:54:09.318089350 +0530
Modify: 2020-02-09 21:54:28.879016531 +0530
Change: 2020-02-09 21:57:54.578250783 +0530
 Birth: -