Internet slow on TPG nbn.

[Brianau13]

Subscribed TPG 250MB/s fibre nbn service. It is quite often to have slow and lagging internet experience at night. FaceTime - lagging seriously, YouTube very slow, FB/IG photos loading very slowly. When I test the speed online, it appared to be 250MB/s. No idea why on one hand those apps are lagging, while the speed test showed 250MB/s. Please advise. Thanks. 

[kate_]

We want to make sure you're able to use your internet to its full potential, @Brianau13!

Are you seeing this lagging on all of your devices, or only some? Do you see any difference after giving your modem a restart?