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There are many factors that can affect the speed of an NBN service. Depending on the access technology, the actual throughput speeds may be slower and could vary due to many factors including the type or source of the content being downloaded, the number of users and devices that simultaneously use the service, the way the service is being used from wired or wireless connection, the number of users that is connected using the network infrastructure for different service.
We've checked your account and it appears that you are under the old NBN25/5 plan. You have the option to upgrade to the new NBN50/20 plan that starts at $69.99/Month. This will give you more internet speed. You may also add a home phone add-on for the phone service. You may check our website for more information here.
If you decided to upgrade your plan, then you may follow the steps here: How to Change NBN Plan Online via TPG My Account