Techno-useless Car hire

I have been trying to use their website to make a booking for the past two days. The website does not work- it cannot process a completion. The mobi-website is full of glitches. I now have 2 bookings showing on my profile. One needs cancellation and the other needs a time adjustment as I am returning later than picking up. The call center is useless as they cannot make amendments to online bookings. The 40% special ends today. Lets see how this goes.