Spacebar not functioning for Flight/Divine-Ascend

[Simple_Barghest]

Date & Time: 1/16/2021
Frequency: Erratic. Occurred twice on previous day, is still ongoing today.
World name: Midgardsormr
Character name: Wren Blackwing
Retainer name: None
NPC name: None
Monster name: None
Class/Level: Dark Knight/80, but the Job involved has not mattered.
Party or solo: Has occurred Solo thus far, but if Diving qualifies it could occur in Rabanastre during the underwater portion.
In-game time: Server Time 4:03 PM
Area and coordinates: Previously occurred in The Tempest, today occurred in Mor Dhona
Housing: None

Steps:
I have no idea what steps to take to recreate this bug, so I will simply explain it in full.
Twice now the Spacebar has not functioned for its purpose in Ascending when on a Flying Mount, and have not tested it but presumably it would apply when Diving, such as in The Ruby Sea. Spacebar still works for its intended purpose of Jumping when on ground, and functions for both Manual and Automatic variants of the Flying Mount Takeoff setting.

The first period, in The Tempest, was fixed twice. The first time, was done via adjusting the Flying Mount Takeoff setting to its inactive version (in that instance, went from Manual to Automatic). The second time, that fix did not function, but logging out of that character and then logging back in fixed it.

Currently today, neither of the previous fixes have worked. Neither has zone transitioning from Mor Dhona to Northern Thanalan, neither has fully exiting the game and then restarting the application fixed it.

As I know the point of Keybinds will be brought up: The only keybinds that were modified on this account in any respect were those for Hotbars, to accommodate current hotbar set-up. And yet currently looking at the Movement Keybinds, two things stick out to me:
-The first, is that Flight/Diving-Ascend is Empty, and attempting to assign Spacebar there wipes the current Keybind for Jumping.
-The second, is that the Flight/Diving-Descend keybind is set to Ctrl-Spacebar. Testing this keybind reveals it does not work.