The variable $id does not exist. Did you forget to declare it?
This check marks access to variables or properties that have not been declared yet. While PHP
has no explicit notion of declaring a variable, accessing it before a value is assigned
to it is most likely a bug.
It seems like the type of the argument is not accepted by the function/method which you are calling.
In some cases, in particular if PHP’s automatic type-juggling kicks in this might be fine. In other cases, however this might be a bug.
We suggest to add an explicit type cast like in the following example: