Call centre staff with a bad attitufe

I understand that it is the festive season and that the call centre staff are tired and overwhelmed with calls. However that is NO excuse for them to be snappy and rude to clients calling to inquire on a delivery. She answered the phone with low energy and had an attitude immediately when I explained I'm querying my package. She was telling me about 5-7 working days which is fine and expected, but when I receive a notification via email telling me that my parcel is out for delivery and would arrive in a day or 2. I expect that it will be delivered in a day or 2 as per the last communication sent from the company. The consultant did not give me a chance to explain this and she disconnected the phone. I still have not received my package or any notification to inform me of any delay more than 1 or 2 days.