How to fix this Warning being shown on my website

hi folks
A couple of days ago one of my websites started displaying the following error message at the top of every page:

Warning: mysql_fetch_array(): supplied argument is not a valid MySQL result resource in /home/username/public_html/includes/functions.php on line 355
Warning: mysql_num_rows(): supplied argument is not a valid MySQL result resource in /home/username/public_html/includes/functions.php on line 388
Click to expand…

The code on line…
How to fix this Warning being shown on my website

See original post by mistermix