I Agree with you there is no Coincidences , but in some cases we need time to know what is the reason of its and investgate deeply to reach to the solution in the end

We should be careful to not overstate the case. "Coincidence" typically means 'some surprising convergence of events lacking obvious connection'. If so, then there are often coincidences, e.g. my partner and I independently order fish for dinner.

I suspect by "coincidence" you mean something like 'event arising for no reason' where by "reason" you mean something like 'objective, fundamental reason.' In other words, there is at base some objective reason - whether we know it or not - for every event. I'm sympathetic; that seems true to me.

NOTE 1: If we mean by "coincidence" that converging events be simultaneous, then assuming General Relativity is true, there are no simultaneous events, and so no coincidence.

NOTE 2: If the principle "There is at base some objective reason for everything" is not restricted to, say, events, then we can ask what is the basic objective reason for the principle itself. That seems incoherent.

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