I need your help, friends.
I use Open Cart 3, and when I check my logs i view this error:

```
[11-Jan-2020 04:12:05 UTC] PHP Fatal error:  Uncaught Exception: Error: MySQL server has gone away<br />Error No: 2006<br />SELECT * FROM oc_currency in /home/nnhmetwhlxad/public_html/system/library/db/mysqli.php:40
Stack trace:
#0 /home/nnhmetwhlxad/public_html/system/library/db.php(45): DB\MySQLi->query('SELECT * FROM o...')
#1 /home/nnhmetwhlxad/public_html/system/library/cart/currency.php(10): DB->query('SELECT * FROM o...')
#2 /home/nnhmetwhlxad/public_html/catalog/controller/startup/startup.php(160): Cart\Currency->__construct(Object(Registry))
#3 /home/nnhmetwhlxad/storage2/modification/system/engine/action.php(79): ControllerStartupStartup->index()
#4 /home/nnhmetwhlxad/public_html/system/engine/router.php(67): Action->execute(Object(Registry))
#5 /home/nnhmetwhlxad/public_html/system/engine/router.php(46): Router->execute(Object(Action))
#6 /home/nnhmetwhlxad/public_html/system/framework.php(165): Router->dispatch(Object(Action), Object(Action))
#7 /home/nnhmetwhlxad/public_html/system/startup.php(104): require_once('/home/nnhmetwhl...')
#8 /ho in /home/nnhmetwhlxad/public_html/system/library/db/mysqli.php on line 40

```