It's been over 180 days since my last 3x CLI. Last time, I was instantly approved. I tried this morning and got a "7-10 days" message so I think I got denied. Not even a counter offer. 
@Anonymous wrote:It's been over 180 days since my last 3x CLI. Last time, I was instantly approved. I tried this morning and got a "7-10 days" message so I think I got denied. Not even a counter offer.
Same thing happened to me. Happens more than people think. Amex CLIs are certainly not guaranteed despite the perception that they give them out like candy. Just try again in 90 days and address whatever issues they cite if you are indeed declined.
For some reason this thread inspired me to ask for a CLI as I noticed it had been about 9 months since I got the one to 10k. Asked to be bumped to 15k and was instantly approved. I agree with the others to try your luck again after a little time has passed.
Got my "key reason" for denial.
Length of time as a customer is too short.
UPDATE:
Tried again 90 days later. Asked for $18k but they countered with $15k. Of course I accepted. 
I did not relaize they keep doing the 3X CLI after the intial one. I am sitting at 28K limit right now, and this has me tempted to see how high I can go 
@Mattopotamus wrote:I did not relaize they keep doing the 3X CLI after the intial one. I am sitting at 28K limit right now, and this has me tempted to see how high I can go
Just be ready, usually (not always) any higher than 25k they will request a 4506-t to approve you. Not that it is the worst thing in the world, but sometimes it is more information then people want to give out for a CLI.