F5 iRule for X-Country-Code not working as expected

Thanks Jeffrey_Granier, I tried the code below which resolved my issue. Thanks for your support.

when HTTP_REQUEST {
    if {[HTTP::uri] starts_with "/java"} {
        set country_code [whereis [IP::client_addr] country]
        log local0. "Matched /java - client IP: [IP::client_addr], country: $country_code"
        set session_key "country_[TCP::client_port]"
        table set $session_key $country_code 300
    }
}

when HTTP_RESPONSE_RELEASE {
    set session_key "country_[TCP::client_port]"
    set country_code [table lookup $session_key]
    if {$country_code ne ""} {
        log local0. "HTTP_RESPONSE triggered for session $session_key, country: $country_code"
        HTTP::header insert "X-Client-Country-Code" $country_code
        log local0. "Added X-Country-Code: $country_code to response"

        # Clean up the session table
        table delete $session_key
    }
}