Then the local service provider you used is in error.
We got a 4M/4M with full guaranteed bandwidth connection from you.
Not 2, not 1.5M. 4M.
1.4M which is what we have on the graphs, which is nowhere close to that guarantee.
This also matches our own records.
The circuit should be able to cope with that usage without issue.
Please push our local partners and advise soonest.