Although i havent worked on Huawei phones before, as a general rule issues where a screen works for a while and then stops means the circuit in the lcd itself is bad and it needs a new screen. I cant guarantee this is the issue, but hopefully this helps you get a little closer to a solution.
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=== Update (06/03/2018) ===
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Apologies. I read that wrong. I thought you said lcd. If u tried cleaning the connection off then you probably need a new digitizer unfortunately
Although i havent worked on Huawei phones before, as a general rule issues where a screen works for a while and then stops means the circuit in the lcd itself is bad and it needs a new screen. I cant guarantee this is the issue, but hopefully this helps you get a little closer to a solution.