When I charge my phone my phone is saying charging slowly why how can

Start with the basics:

1. check whether it supports fast charging and that the adapter you are using also supports it.

2. Are you using the original charging cable?

3. Is the cable or plug damaged? Replace it.

4. Is there a problem with the power adapter? Try a different one, if indicated, replace.

5. Power supply? Trying a different usb port may cure your problem try all of them, does your wall outlet have power?

6. Dust etc.  Interfering with power delivery? Clean your usb port–carefully.

7. Worn or damaged battery, replace.

8.Using it while charging, high screen brightness, and unnecessary background apps also contribute to slow charging. For fastest charging, let it be while it's having dinner.

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