Why doesn't the assembly code produce desired output?

Question

.model small
.stack 100h
.data
    msg1 db '2 - 5 = $'
    result db '-$'
.code
main proc
    mov ax, @data
    mov ds, ax

    ; subtract 5 from 2
    mov al, 2
    sub al, 5
    aas
    
    ; print the result as -3
    mov ah, 9
    lea dx, msg1
    int 21h
    
    ; check if the result is negative
    cmp ah, 0
    jz print_positive
    
    ; if the result is negative, print a '-' character
    mov ah, 2
    mov dl, '-'
    int 21h   
    
    ; convert the absolute value of the result to ASCII characters
print_positive:
    mov ah, 0
    neg al ; negate the result to get the absolute value
    add al, 48
    mov result+1, al
    mov ah, 2
    lea dx, result
    int 21h
    
    mov ah, 4ch
    int 21h
main endp
end main

This code is for 8086 microprocessor to perform subtraction and show negative number on the screen.

I write the code so that it produces 2-5=-3 on the screen. But it doesn't print 3. It prints 2-5=-. Any reason why?