The Professional Couriers - The courier did not reach even after passing a week

Hi

I have sent a courier on last thursday through Professional couriers tracking number HYD16087119. The address is also in hyderabd. He said it will take atmost 2 days to reach as it is a local one. But till now, it did not reach. When I check the status of the courier in their official site, it is showing as "On Transit". I do not know what does it mean. There is nothing stated in the site about the status and its meaning. I have got only the customer service number in the bill 040-27813344. But I have been trying to contact the number lot number of times, it says only one message "The number you are trying is busy, please call after sometime". I dont know at what time should i be calling them. This is the only number that is specified in their official site aswell.