The diagram shows a display with five letters, with up and down arrows surrounding each letter, and an upside-down 'Submit' button below the layout.

On the Subject of Not Passwords

Unfortunately this password doesn’t seem to meet standard KTaNE password standards: 25 letters, mixed up, spell a word with the length of 5 letters, module defused, happy fun time for all.

The buttons above and below each letter will cycle through all the letters within that column. There will be no duplicate letters between all of the columns, which means 25 of the 26 letters will be present on the module. Find the one letter that is missing, and follow the instruction associated with that letter.

* If you are instructed to hold a button for a certain number of seconds, hold the button and release it after that many ticks of the bomb timer.

Missing letter Instruction
A Press the Submit button when the bomb timer has a 5 in any position.
B Press the Submit button when the right-most seconds digit on the bomb timer is not prime.
C Hold the Submit button when the bomb timer has a 7 in any position, and release when it has a 2 in any position.
D Press the Submit button when the right-most seconds digit on the bomb timer is prime or zero.
E Hold the Submit button for exactly 4 seconds.
F Press the Submit button twice quickly.
G Hold the Submit button when the bomb timer has a 6 in any position, and keep holding it until the module is solved.
H Press the Submit button once, wait for 5 seconds, then press it again.
I Press the Submit button when the bomb timer has a 1 in any position.
J Press the Submit button three times quickly.
K Press the Submit button.
L Press the Submit button when the minutes left on the bomb timer is an even number.
M Hold the Submit button and release it when the bomb timer has a 3 in any position.
N Hold the Submit button for exactly 8 seconds
O Hold the Submit button, and keep holding it until the module is solved.
P Press the Submit button when the bomb timer has a 7 in any position.
Q Press the Submit button twice quickly
R Hold the Submit button for exactly 3 seconds.
S Hold the Submit button when the bomb timer has a 4 in any position, and release when it has a 3 in any position.
T Hold the Submit button when the bomb timer has a 3 in any position, and keep holding it until the module is solved.
U Press the Submit button once, wait for 2 seconds, then press it again.
V Press the Submit button five times quickly
W Press the Submit button when the bomb timer has a 2 in any position.
X Keep pressing the Submit button quickly until the module is solved.
Y Press the Submit button.
Z Hold the Submit button for exactly 10 seconds