by Ken Task.
The use of 'set global' is temporary. If one restarts MySQL any variable set via set global is reverted to defaults.
Your settings show:
| max_allowed_packet | 16777216 - Is 16M
Make the setting in my.cnf and restart mysql.
Then check via command line/mysql client:
SHOW VARIABLES LIKE 'max_allowed_packet'
'spirit of sharing', Ken