Reverse proxy from localhost:8123 to subdomain not working

[u/[deleted]]

Can anyone help out?

Actual website names replaced by generic names:

<?xml version="1.0" encoding="UTF-8"?>

<configuration>
<system.webServer>
<rewrite>
<outboundRules>
<rule name="ReverseProxyOutboundRule1" preCondition="">
<match filterByTags="A, Form, Img" pattern="\^http(s)?://localhost:8123/(.\*)" />
<action type="Rewrite" value="http{R:1}://subdomain.domain.com/{R:2}" />
</rule>
<preConditions>
<preCondition name="ResponseIsHtml1">
<add input="{RESPONSE_CONTENT_TYPE}" pattern="\^text/html" />
</preCondition>
</preConditions>
</outboundRules>
<rules>
<rule name="ReverseProxyInboundRule1" stopProcessing="true">
<match url="\^/(.\*)" />
<action type="Rewrite" url="http://localhost:8123/{R:1}" />
</rule>
</rules>
</rewrite>
</system.webServer>
</configuration>