I'm trying to rebuilt the tutorial model but i'm stuck at step 1.4. Somehow, the first customer to arrive in my system does not remains in the waiting line though settings of the queue Waiting Line are as according to the manual (the move activity is set to move a customer to the waiting line). When it should move the customer into the waiting line, it suddenly jumps to an empty place in the model.
I would like to understand why this is happening and how I can fix it. Thank you in advance.