This ready made https://www.google.com/search?source=hp&q=after+effects+alternative link has lots of alternatives
As for your direct problem, with no operating system or browser information there is no way for anyone to help
If you do go to Chat, you will need to provide the missing information
Be sure to remain signed in with your Adobe ID before accessing the link below
Creative Cloud support (all Creative Cloud customer service issues)
I'm on MacBook Pro Safari, I click "Buy" for AE 2015.3 a new white blank window opens with a box made of 4 flashing boxes in the middle and no other instructions - so what am I supposed to do to continue to buy AE? If I click on the ADOBE logo on top right it just takes me to the Adobe homepage. I called costumer service and it was horrible - they call back but you still have to wait 10 min for someone to actually come on the phone, after taking my info the guy transfers me to another dept. saying the wait will only be 1-2min, after waiting over 10 min I gave up and hung-up
Thanks for the AE alternative software links - maybe better go w/ something non-Adobe than trying to get thru thier 'customer service'