My wife took a trip on an American Airlines 777-200 in business class, and the "lie-flat" seat didn't seem to work right; she is only 5' 4" tall and said she could not fit in the seat laying flat without curling up her legs. Was the seat defective or hard to program to be totally lie-flat? I read some travel blogs and I have not heard this complaint before on lie-flat seats.
The seat pitch in either of the two 777-200ER Business Class products (Aerospace Super Diamond or Zodiac seats) have a maximum seat pitch of 60-61", and that usually is what you get when the seat is lay-flat, plus a few extra inches in a cubbyhole under the seat in front of you.
I cannot find any measurements of an actual lay-flat bed end to end for either of American Airlines configurations, but it would not surprise me that a 5'4" person would have issues - I certainly do at 5'10", but thats a whole different story. My wife on the other hand is around 5'2" and often still has issues with Business seats in lay-flat configurations.
Remember, these lay-flat seats aren't designed to be the best bed in the world, you aren't going to get a king single for example, but you are going to get something you can get more sleep in than you would otherwise.
American Airlines has two versions of the 777-200. See https://www.seatguru.com/airlines/American_Airlines/American_Airlines_Boeing_777-200ER_E.php
If you remember your seat number, you can check where you actually were sitting. All business class seats are full lie flat, i.e. they are angled to overlap and hence you get a decent flat area that should have been plenty of space no problem for a 5'4" person.
If there are any problems with the seat, the flight attendant will be happy to help and assist. Some of the more fancy seats are not straight forward to operate so asking for help is always ok
Thanks for the good suggestions and resources. Now we are back home, I can mention on our return trip, my wife had the same issue, and I had her call the flight attendant per one of the answers. Unfortunately the flight attendant couldn't figure it out, but my wife did; she just had to scoot up in her seat when it was flat. I noticed when I was seated the headrest was pretty high, so I figured that might be the trick. So when I finally was ready to sleep, I set the seat flat and scooted up in my seat and I fit (just barely) and I'm 6'-0" tall. One note: lie-flat didn't mean lie level... I didn't think to use the bubble level app, but I was on a slight slope but at least my head was higher than my feet!