HTTP FORWARD PROXY IAPP IRULE NOT WORKING

How can i get the HTTP FORWARD PROXY IAPP to work effectively. In my environment,i have a requirement to use LTM as a forward Proxy to .i have used the HTTP PROXY IAPP and edited the DNS to reflect the dns server in my environment, and i can confirm DNS is working. However,users can't browse with their proxy ip and port configured on their browsers, even though chat messages are landing

Is there any tweak that needs to be done on Irule or the likes to make it work?.

I will post the irule generated by the iapp in the comments