I only have 1Mb download speed and sometimes less like .50Mbs and its really upsetting because we just got our internet back we bad internet 6 with 100gb of data but we would always go over because we didn't know about HD video streaming. So we got unlimited data but now we only get 1Mbs of download speed and only one person in the house hold can watch Netflix or play online games. We called telus about it and they told us that 1Mbs was the best they have?.. But it makes no sense because what is the point in unlimited data if only one person can really use the internet due to 1Mb of download speed?.
If your previous speed test before this were closer to 6, then I'd say call them again and see if they still have a Solutions team. Is likely your best bet.
Other than the speed drop, what else has changed? New equipment, new wire installation, new internet package, have you moved to a new location? It makes little sense that just buying the upgrade to unlimited data caused a drop in speed as you describe.
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