Initializing it like that only works when you're declaring it
char addr[] = "Cane Gardens";
but not after.
For your case, you can copy a string in directly:
strcpy(account[0].address,"Cane Gardens");
Just remember there is a null character ('\0') at the end of "Cane Gardens," so make sure your address array is big enough to hold whatever you copy to it plus the null.