PHP Deprecated

unserialize(): Passing null to parameter #1 ($data) of type string is deprecated

app/functions/fn.products.php, line: 2850

File:	app/functions/fn.products.php
Line:	2850
Function:	{closure}
File:	app/controllers/frontend/companies.php
Line:	414
Function:	fn_get_products_layout
File:	app/functions/fn.control.php
Line:	722
Function:	include
File:	app/functions/fn.control.php
Line:	458
Function:	fn_run_controller
File:	index.php
Line:	19
Function:	fn_dispatch