Increase wal_sender_timeout to resolve the issue. I've been investigating just this issue recently. See https://www.postgresql.org/message-id/CAMsr+YE2dSfHVr7iEv1GSPZihitWX-PMkD9QALEGcTYa+sdsgg@mail.gmail.com . It would be very useful to me to know more about the transaction that caused this problem.
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Соглашаюсь с условиями обработки персональных данных