Example of a finite category without (co)limits?

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Im looking for a example about a finite category such that limit and colimits doesnt exist. I tried with preordered set and similars ways but I couldnt reach an example. I dont know if its possible. Anyone knows about it?

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You say you tried with preordered sets, but preordered (and even partially ordered) sets without limits and colimits are very easy to find.

Any poset without a least element fails to have an initial object. Any poset without a greatest element fails to have a terminal object. Any poset without greatest lower bounds fails to have products, and any poset without least upper bounds fails to have coproducts.

For an example failing to have all four, take the category with two objects and only identity arrows (the poset with two incomparable elements).