When start run or cycling or walking I get wait message for GPS. It takes very long to make GPS ready. Sometimes it is never ready.
Which device? There are some that are experiencing a delay in GPS acquisition, as mentioned here - GPS lock takes longer in 11.28
But I would start with trux's suggestion.
...additionally you should also perform the soft-reset of the watch - that's always a good precaution, especially after a firmware update, or in case of any problems (no data or settings will be lost): How to Reset My Garmin Outdoor Watch | Garmin Customer Support