Estimated & Real Speeds discrepancy

[#1]

Good afternoon everyone,
I have a query regarding this email:
Dear Miss Adoti,
Account username: folacks
When you signed up for your broadband account, we performed a check on your telephone line to give you an estimated speed your line might achieve.
Now that your service has now been active for 14 days, we thought we'd let you know the speed as it stands today, by way of comparison.
Estimated line speed: 17Mbps
Current line speed: 3.7Mbps
I do not understand how they can be such a significant difference between the speeds I was estimated when I signed up to plusnet and the actual speed I receive.
I have waited a good few weeks before writing this to ensure the above details were correct.  The ticket system does not really give you the option just report a fault in speed discrepancy.
Furthermore, I have found that my connection is never really stable.
An example is that of today where our internet connection was down for over an hour since half three. It came back on around half 4 but it is really very intermittent.
Has anyone experienced this?

[#2]

I am experiencing this problem with a recent fibre connection.  The estimate that Plusnet provided was 31.1 Mbps download but the initial actual speed was 9.2 Mbps and this has now fallen to 7.4 Mbps.  The connection is stable.
I appreciate that the data provided was an estimate but it appears not have been a reasonable estimate ie insufficient care was taken to ensure that the data was a reasonable basis for offering a service.
I raised this problem as a fault with Plusnet nearly 7 weeks ago and they are apparently still having difficulties finding a solution with Openreach.  So far I have been in contact with I think it is 16 different Plusnet support staff.
If you have not already done so I suggest that you carry out all the speed related checks recommended by Plusnet in the 'How to get the best broadband speed' section of the Plusnet site and then, if there is no substantial improvement, raise your speed issue as a fault.
I wish you the best of luck.

[#3]

@Folake
It's difficult for forum members to provide meaningful comment without at least router stats information.
Could post the information listed in this post?
However having an unstable connection might be the cause of the low speeds. You could report a dropping connection fault at http://faults.plus.net.

[#4]

@Folake
Our faults team will be in-touch once we've finished testing your line.
@rbel
I can see we've got an engineer booked for today, sorry this is taking time to resolve.
Let us know how you get on and also a warm welcome the both of you to our community forums.