@anon33584716 @Yme_Quispel @Madina_Khabibulina
RE this thread and No sound when calling
You may be interested to hear that a problem similar to yours, in which the distant caller could not be heard in phone calls on the earpiece, but could be heard on the speaker, was found by askaaron to originate with an incorrect setting in the Phone app.
See askaaron’s link in post #7 above.