Different position moves existing notifications

[Oliver Polden]

Steps to reproduce: (You can use demo at https://carlosroso.com/notyf/)

1. Create a notification in the bottom right.
2. Create anotification in the top right.

Result:
Notification that was in the bottom right moves to the top right and second notification appears below.

Expected behaviour:
First notification appears remains in bottom right and second appears in top right.

Workaround:
Create separate instances for each position.