Step 6 in the following document, http://server.arcgis.com/en/portal/latest/administer/windows/configuring-a-highly-available-portal.htm, does not mention that the first Web Adaptor requires reconfiguration after the reverse proxy is added.

Solución alternativa

Follow the instructions provided in another document, "Configure multiple ArcGIS Web Adaptors", from the following link, https://enterprise.arcgis.com/en/web-adaptor/latest/install/iis/configure-multiple-arcgis-web-adaptors.htm.

Pasos para reproducir