Can’t find noise cancellation in my iPhone 7plus can’t make calls anymore,how to fix this?

If you bought the iPhone used from a non-reputable source, the battery may be fake and showing a false Maximum Capacity %:

About genuine iPhone batteries

(Article found by searching Apple's Knowledge Base.)

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namfxghostNA ~ With an old model of iPhone, it's worth checking for a weak battery...

Does your iPhone 7 Plus still have its original battery?

And what's the Maximum Capacity % here?...

Settings > Battery > Battery Health

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To determine whether the battery is genuine or not, take your iPhone to an Apple location:

Find Apple locations in Namibia (NA)

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85% is unexpectedly high for an original iPhone 7 Plus battery. Did you buy the iPhone new or used?

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namfxghostNA wrote: "...if I buy a new battery will things get back to normal?..."

Nobody here can predict the result.

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namfxghostNA wrote: "But how do I fix this??"

I don't know. Begin by returning to the place you bought the iPhone and ask them whether they replaced the battery with a genuine one or not.

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