Please clarify message "Error loading memory: ASM Emitting unfilled A instruction"

[CodeQuiver]

Hi! I'm working on Project 7 and have encountered this error when trying to upload my StackTest.asm translated file to the CPU Emulator. Can a contributor clarify what specific type of code error this is referring to?

I'm sure my code legitimately has an error, but even after tracing the message and the code that triggers it in the repo, I can't tell exactly what "Emitting unfilled A instruction" is meant to indicate. I don't have any lines that are just "@" with nothing else, which would have been my first guess. Debugging would be much easier if I understood the error. Thanks!

Edit: This appears to show up when the same label is used more than once, but I'm not sure if that's what's intended to be checked or if the error check was for something different but related. Example code:

@EQ_TRUE
D;JEQ
D=0
@EQ_SAVE
0;JMP
(EQ_TRUE)
D=-1
(EQ_SAVE)
...
@EQ_TRUE
D;JEQ
D=0
@EQ_SAVE
0;JMP
(EQ_TRUE)
D=-1
(EQ_SAVE)
...