Own lru_cache decorator in python

Question

I can't understand, why my own decorator "lru cache" doens't work.

def cache(max_size: int):
  
    dictionary = OrderedDict()

    def trace(func):
        @functools.wraps(func)
        def wrapper(*args, **kwargs):
            cache_key = args + tuple(kwargs.items())
            if (cache_key not in dictionary) and (len(dictionary) < max_size):
                dictionary[cache_key] = func(*args, **kwargs)
            elif (cache_key not in dictionary) and (len(dictionary) == max_size):
                dictionary.popitem(last=False)
                dictionary[cache_key] = func(*args, **kwargs)
            else:
                old_cache = dictionary[cache_key]
                del dictionary[cache_key]
                dictionary[cache_key] = old_cache

            return dictionary[cache_key]

        return wrapper

    return trace

@cache(20)
def binomial(n: int, k: int):
    if k > n:
        return 0
    if k == 0:
        return 1
    return binomial(n - 1, k) + binomial(n - 1, k - 1)

binomial(30, 1)

ERRORS:

Traceback (most recent call last):
  File "main.py", line 33, in <module>
    binomial(30, 1)
  File "main.py", line 13, in wrapper
    dictionary[cache_key] = func(*args, **kwargs)
  File "main.py", line 31, in binomial
    return binomial(n - 1, k) + binomial(n - 1, k - 1)
  ...
  File "main.py", line 13, in wrapper
    dictionary[cache_key] = func(*args, **kwargs)
  File "main.py", line 31, in binomial
    return binomial(n - 1, k) + binomial(n - 1, k - 1)
  File "main.py", line 13, in wrapper
    dictionary[cache_key] = func(*args, **kwargs)
  File "main.py", line 31, in binomial
    return binomial(n - 1, k) + binomial(n - 1, k - 1)
  File "main.py", line 18, in wrapper
    old_cache = dictionary[cache_key]
KeyError: (10, 0)

As I understand, that is just recursive errors, but I can't understand why they appear.

I tried to run this decorator on fibonachi numbers function (fib(10)) with cache capacity of 3, but it return an error. WHY?