Lighting the street, problem

Hello everyone, I have a question. In my scene, it’s all dark street, I just want 3 or 4 spot light in some positions in the screen. But if I make more than 2 spotlights, the lights just gets crazy and some problems occur. Let me explain it with pictures :

First 2 lights, it’s good.

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But and than, when I add the third light some light lines just occurs and it seems so bad

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try to change the quality setting to Fantastic for the editor