make sure that you're increasing the call volume and not media volume. To ensure that you increase the call volume go into settings>sounds and vibration>volume> Then proceed to increase the ringtone to your preferred level.
Hey there! Let’s run through a quick Hardware Test on your phone. To do this head over to your dial pad any type in *#0*#, this will bring up a number of tests. From there, tap on Speaker. This will play a tone over the speaker, does this seem quiet too?
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