Terrible service - Still waiting for my order after a month!

I placed my order on 13th December 2019. My order was partially delivered around 23rd December (i.e. only 1 of the 2 products was delivered).

I've been checking the order status and it was saying "Partially Dispatched" after the 1 item was delivered.

When I logged in on 8th January to check again, it showed the order is "Dispatched", but I still have not received my second item and if I go to the tracking, there is NO update on the order since 23rd December when the first item was delivered.

Where is the other half of my order and when will I receive it? As it has been almost a month since I placed my order. Usually only when an order is delivered and all items have been received by the purchaser, does the status change to "Dispatched"; and yet, here I am sitting still waiting for my delivery but the order status is "Dispatched". When I placed my order it indicated I would receive the package within 5 to 10 working days...It has now been almost A MONTH@

I've tried logging a ticket on onedayonly's support system (I logged it yesterday at 10am and still have not received ANY response). I've tried calling onedayonly TWICE during their operating hours but no one answers the phone and it gets redirected only to then indicate "The number you have dialed is unavailable at present".