NASM Windows ReadConsole NumberOfCharsRead Buffer - winapi

Question

I am attempting to convert an existing assembly program that I have so that it works on Windows. It should ask the user for their name and then output "Hello name". I pretty much have it working but there is a problem with getting the number of characters actually read from the ReadConsole call.
My program is:
extern ExitProcess ;windows API function to exit process
extern WriteConsoleA ;windows API function to write to the console window (ANSI version)
extern ReadConsoleA ;windows API function to read from the console window (ANSI version)
extern GetStdHandle ;windows API to get the for the console handle for input/output
section .data ;the .data section is where variables and constants are defined
hello db 'Hello ' ;db stands for 'define byte'
length equ $-hello ;get the length of the hello
;$ is the current memory location
;$-hello means the difference between the current location and
;where hello started
enter_name db 'Please enter your name: '
name_len equ $-enter_name
chars dd 0
section .bss ;the .bss section is where space is reserved for additional variables
name:
resb 30 ;reserve 30 bytes of space for the name
char_written:
resb 4
section .text ;the .text section is where the program code goes
global _main ;tells the machine which label to start program execution from
_main:
;get the output handle
mov rcx, -11 ;specifies that the output handle is required
call GetStdHandle ;returns value for handle to rax
;print message asking user for their name
mov rcx, rax
mov rdx, enter_name ;load the address of enter name message into rsi
mov r8, name_len ;move the length into the rdx register
mov r9, char_written
call WriteConsoleA
;get the input handle
mov rcx, -10 ;specifies that the input handle is required
call GetStdHandle
;get value from keyboard
mov rcx, rax ;place the handle for operation
mov rdx, name ;set name to receive input from keyboard
mov r8, 30 ;max number of characters to read
mov r9, chars ;stores the number of characters actually read
call ReadConsoleA
;print 'hello' + user's name message
;get the output handle
mov rcx, -11 ;specifies that the output handle is required
call GetStdHandle ;returns value for handle to rax
;print message asking user for their name
mov rcx, rax
mov rdx, hello ;load the address of enter name message into rsi
mov r8, length ;move the length into the rdx register
mov r9, char_written
call WriteConsoleA
mov rcx, -11 ;specifies that the output handle is required
call GetStdHandle ;returns value for handle to rax
;print name
mov rcx, rax
mov rdx, name ;load the address of enter name message into rsi
mov r8, chars ;move the length into the rdx register
mov r9, char_written
call WriteConsoleA
;exit the program
mov rcx, 0 ;exit code?
call ExitProcess
The way that I have read the Windows API documentation on ReadConsole is that it requires the following parameters:
Output Handle
Place to put the read data
A value for the number of characters to read
Place to put the actual number of characters read
I have defined a label name to receive the characters and chars to receive the actual number of characters.
The read call looks like this:
;get the input handle
mov rcx, -10 ;specifies that the input handle is required
call GetStdHandle
;get value from keyboard
mov rcx, rax ;place the handle for operation
mov rdx, name ;set name to receive input from keyboard
mov r8, 30 ;max number of characters to read
mov r9, chars ;stores the number of characters actually read
call ReadConsoleA
My assumption is that if the name entered is Anna then the value 4 or 5 (including new line character) should be stored in chars. This does not seem to be the case as when I attempt to output the name I get nothing with this code:
mov rcx, -11 ;specifies that the output handle is required
call GetStdHandle ;returns value for handle to rax
;print name
mov rcx, rax
mov rdx, name ;load the address of enter name message into rsi
mov r8, chars ;move the length into the rdx register
mov r9, char_written
call WriteConsoleA
But if I switch the chars label out for a value it works as expected i.e.
mov rcx, -11 ;specifies that the output handle is required
call GetStdHandle ;returns value for handle to rax
;print name
mov rcx, rax
mov rdx, name ;load the address of enter name message into rsi
mov r8, 4 ;move the length into the rdx register
mov r9, char_written
call WriteConsoleA
Obviously I am doing something wrong with this buffer - any assistance would be much appreciated.