I experienced similar slower speeds a few months ago, also after a thunder storm. Syncing 8000 mbps as opposed to 22000 mbps. Did some extensive testing through the phone with Support and had a technician come out.
There was some errosion on my phone socket, but turns out the issue was with my modem all along. After ordering a replacement (of the same model) - back to 22000 mbps again
Would recommend you try with a separate modem if possible and see if your milage varies. I didn't believe storms could affect modems but this really was the case. If a separate modem yields similar results, might be your phone line/connection/socket etc.
Welcome to TPG Community!
We were able to locate your account using your community details and have run some remote test. We've detected a fault on the line, but can't verify if it's internal or external wiring.
Please shoot me a private message with your preferred time and best number to be contacted and I'll arrange a call from our Tech team to look into it further.
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