You are getting this error because you trying to access an object property, using the array square bracket or the object property is of the form 'user name' or 'user-name'.

Normally when we want to access an object in php, we make use of the arrow pointer like

$obj_user = new stdClass;
$obj_user->name = "smith john";
$obj_user->username = "smith";
$obj_user->id = "1002";
$obj_user->email = "smith@nomail.com";

But when you try to access an object as

obj_user['name']

OR

obj_user['my name']

This will throw the "Cannot use object of type stdClass as array"

Fixing the error

Cast the object to an array

$obj_user = new stdClass;
$obj_user->name = "smith john";
$obj_user->username = "smith";
$obj_user->id = "1002";
$obj_user->email = "smith@nomail.com";

//Casting the object to an array 
$obj_user = (array)  $obj_user;

echo $obj_user['name']; //smith john

Accessing the data with {}

$obj_user = new stdClass;
$obj_user->name = "smith john";
$obj_user->username = "smith";
$obj_user->id = "1002";
$obj_user->email = "smith@nomail.com";

//Accessing with curly bracket
echo $obj_user->{'name'};

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