I came here to check this old thread because I'm having trouble with ecerts also. I have several of them from the "spend $10,000, get an ecert" credit card benefit. I'll try [MENTION=779880]Shanahoe[/MENTION]'s suggestion... book first and then add. Amazingly, clicking the "book using an ecert" doesn't get the ecert rate, at least as far as I can tell. No hotel for any dates has been available. sigh...

Edited to add: It's still not working for me. No attempted hotels in any city are working. Is there a trick to which rate to choose? Since there's only about 6 rate options per room. Plus, for additional aggravation, there's the annoyance of the grey overprinting on each fill in box which makes it hard to read.