Ebucks Travel nightmare

I booked my flights with ebucks travel. I now urgently need to change my booking. I cannot change it on the airlines website and was told to get hold of ebucks travel. I have been on hold now a few times for up to an hour only to have the call dropped. I emailed them and say said they would get holf of me in 48 hours. only the scheduled flight is in 48 hours, I require my flight moved to the 19th of June. Ive requested someone contact me on my chinese mobile number + ********** ********** or on via email without any assistance. This matter is urgent.