Weird errors

My code was working fine, came back 3 hours later made a small change and getting this error - same error if I go back to my original code.

WARNING: Expecting a number or something iterable, got undefined
Uncaught ReferenceError: "Uint8Arsay" is not defined
 at line 2 col 47
...176|a,0,16],f),b.write(new Uint8Arsay(this.buffer,g*a,g));c....
                              ^
in function "flip" called from line 347 col 10
  g.flip()

What is causing something like a type to get corrupted ?