Used Mission Hub to define mission and simulated it using VLM. Started Mavic Air and took off, in FPV mode. Downlink signal excellent. PGPS mode with 11-13 satellites. Switched to Waypoint and downloaded mission to Mavic Air. Started mission. Displayed "initializing" for more than two minutes until I cancelled the mission and flew it in FPV mode. No error indication from Airdata. No warnings or messages from Litchi (Android, latest Litchi version). Using ASUS P008J tablet. Latest aircraft and controller firmware. Any ideas or advice? Have not tried another phone or tablet.