MyBB SQL Error

MyBB has experienced an internal SQL error and cannot continue.

SQL Error:
1021 - Disk full (/tmp/#sql-temptable-2ac496-477919-641f8.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
Query:
SELECT * FROM myadvertisements_advertisements WHERE zone=3 AND (expire>1712729737 OR unlimited=1) AND disabled=0 ORDER BY RAND() LIMIT 1