Error: conflicting types when trying to make a simple syscall

I'm brand new to Linux programming and I'm trying to implement a simple system call loosely following this guide: https://medium.com/anubhav-shrimal/adding-a-hello-world-system-call-to-linux-kernel-dad32875872. In my linux kernel directory, I created a new directory called my_syscall. Within that directory, I created my_syscall.c. Here is my_syscall.c

#include <linux/syscalls.h>
#include <linux/kernel.h>

asmlinkage long sys_my_syscall(int i) {
   prink(KERN_INFO "This is the system call.");
   return(0);
}

I then created a Makefile in the my_syscall directory with a single line:

obj-y := my_syscall.o

I then edited this line in the Makefile in the kernel directory to be:

core-y         += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/ my_syscall/

Then, in the directory linux-5.4.15/arch/x86/entry/syscalls, I edited the syscall_64.tbl to include the following line at the very end:

548     64         my_syscall          sys_my_syscall

Finally, in the directory linux-5.4.15/include/linux, I edited the syscalls.h file to include this line before the #endif:

asmlinkage long sys_my_syscall(int i);

Now, when I run the command sudo make, I run into the following error soon after:

./arch/x86/include/generated/asm/syscalls_64.h:2664:19: error: conflicting types for 'sys_my_syscall'
__SYSCALL_64(548, sys_my_syscall, )

arch/x86/entry/syscall_64.c:18:60: note: in definition of macro '__SYSCALL-64'
  #define __SYSCALL_64(nr, sym, qual) extern asmlinkage long sym(const struct pt_regs *);

In file included from arch/x86/entry/syscall_64.c:7:0:
./include/linux/syscalls.h:1423:17: note: previous declaration of 'sys_my_syscall' was here
 asmlinkage long sys_my_syscall(int i);
                 ^
make[3]: *** [arch/x86/entry/syscall_64.o] Error 1
make[2]: *** [arch/x86/entry] Error 2
make[1]: *** [arch/x86] Error 2
make: *** [sub-make] Error 2

I have no idea how to approach this error. With a conflicting types error, I would think I declared the syscall differently in someplace, but in both my_syscall.c and the syscalls.h files, the declaration is the same. These were the only two files where the syscall is declared, but it is also named within syscall_64.tbl and it seems like this is where linux is trying to point me towards. However, I don't see what's wrong with how I declared it in the table as I followed the guide directly. Any help with this would be greatly appreciated!

Info:

Kernel version: 5.4.15

Linux Distribution: Ubuntu 14