Why am i not able to hear what the other person while after call records?

[Android Central Question]

I was using an automatic call recorder app for a month or 2,and it was working fine until today, i had to re-listen one caller, where i found that i am not able to here his voice but only mine. Then i thought this was happening for all the other calls as well. But after checking a couple of other records i realised that the problem is only with that particular number. I tried calling him again after installing a new app, still i am not able to here his voice. I tried calling other numbers and checked, but i am able to here other callers voice except for this particular caller. I want to know if it is possible to block from being recorded by someone or any apps available in the market for the same. One thing i know is that he is using an IPhone 8,if that helps

 

[Rukbat]

There are a few things that could keep the call from being recorded - a loud sound, but too high pitched for you to hear, coming from his phone, or from his carrier, would do it. There's no app he can run on his phone that would turn off recording his voice on your phone, though.