Speedtest not matching IP Profile

[#1]

My IP profile has been changing a bit recently. When I first joined it was 38Mb for a few months (recommending speed was 21Mb) it dropped and dropped until it stayed static at 24Mb. I complained to PN about it as it was perfectly stable at 38Mb but nothing came of it. Now it's started going back up and is currently at 29Mb. Until this week I had been getting speed test results of 26Mb now I'm consistently getting 20Mb and it will not go past 20 despite my IP profile being set to 29Mb.
Anyone have any ideas?

[#2]

Hi there,
Your BT profile has been reduced due to the exchange picking up a sync rate of 21520 on your line yesterday. Hopefully it'll uplift again but that's what's caused the slowdown - couldn't tell you what's caused it to suddenly sync at a slower rate though I'm afraid. If the sync speed picks up it should improve - hope that happens soon for you.

[#3]

Speedtest still reporting 20Mb and no higher, IP Profile on the plusnet site still saying 29Mb. Can you take another look for me please?

[#4]

Hi, the profile on BTs side hasn't changed I'm afraid - it's still showing the last record picked up as being 21520 on the 17th. I'll reduce your profile on our side to 20800 match it so the traffic management works correctly.