When calling from abroad receiver can't hear me

[Corwil]

I can call my sister on her landline while I'm abroad and she can hear me but the other day my bank requested me to call them back and although could hear them speak they could not hear me. Confused ! 

[bristolian · Accepted solution]

When abroad you are roaming on foreign networks, over which EE have no direct control.

Try manually connecting to alternative operators in your host country and see if the symptoms are the same.

[Corwil]

Thank you I understand. I did also try to sit closer to the router and somehow it did the trick.