A buyer is trying to rip me off

[akaway]

Hello, I’m explaining my problem.
I have been working with a person on Fiverr for a month now.
There have been several orders and everything has been running smoothly.
However, the buyer started to blame me because according to him “the video has a black screen” or “my work is not professional”.
What I don’t understand is that the buyer never told me there was a problem before.
What can I do at a time like this?

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[imagination7413]

Sounds like you should block this buyer after you complete the next order. Set your boundaries now.