DFA - Accept all strings that does not contain a certain substring [duplicate]

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So I have been trying to create a Deterministic Finite Automaton(DFA) in Jflap that accepts all strings from the alphabet {a, b, c} except those that contain the substring "abc". However i keep running into issues where certain strings that should be allowed aren't, such as "acbc". Do you have any tips or tricks that can be used to get around these kind of issues?

DFA that accepts any string that contains substring "abc" below