( ! ) Fatal error: Default value for parameters with a class type hint can only be NULL in /home/users/1/at-office/web/otaketakahirocom/wp-content/plugins/simple-membership/classes/class.swpm-transactions.php on line 173
Call Stack
#	Time	Memory	Function	Location
1	0.0001	220336	{main}( )	.../index.php:0
2	0.0002	222928	require( '/home/users/1/at-office/web/otaketakahirocom/wp-blog-header.php' )	.../index.php:17
3	0.0003	240664	require_once( '/home/users/1/at-office/web/otaketakahirocom/wp-load.php' )	.../wp-blog-header.php:13
4	0.0004	252888	require_once( '/home/users/1/at-office/web/otaketakahirocom/wp-config.php' )	.../wp-load.php:50
5	0.0011	434064	require_once( '/home/users/1/at-office/web/otaketakahirocom/wp-settings.php' )	.../wp-config.php:93
6	0.3688	51427296	include_once( '/home/users/1/at-office/web/otaketakahirocom/wp-content/plugins/simple-membership/simple-wp-membership.php' )	.../wp-settings.php:418
7	0.3708	51784784	include_once( '/home/users/1/at-office/web/otaketakahirocom/wp-content/plugins/simple-membership/classes/class.simple-wp-membership.php' )	.../simple-wp-membership.php:33