I have the Fox on a couple bikes and Reverb on a couple others.
The FOX post seems to develop a lot of stiction around the seal and that can prevent it from fully returning to max height. There are various short term fixes for this including using a zip-tie to drop a little oil (or FOX fluid) into the seal, using a little Slick Honey or SRAM Butter along the post, or a partial rebuild. Google and you’ll find instructions on all three of those approaches.
I clean the post and apply Slick Honey every 10-12 rides. That seems to help quite a bit with a post having sticky return but no other issues.
You should also check your dropper lever at the bars, the cable and the cable adjustment as that can affect the dropper function on the FOX post.
Excessive play, assuming you mean side to side movement of the saddle, can be a sign that you need to have a rebuild. FOX posts are more difficult to do at home compared to the Reverb so probably send it out for that service. That said, check your seat and seat post clamp before jumping to a rebuild. Seats break and clamps can loosen up so check the easy stuff first.
Good luck. Droppers are brilliant but they do require maintenance time to time.