I received a call from a consultant regarding my Fibre Connection, i expressed my concern regarding my Fibre speeds that have been getting slower day by day

I received a call from a consultant regarding my Fibre Connection, i expressed my concern regarding my Fibre speeds that have been getting slower day by day. I was told to submit a callback request and someone will contact me to do a diagnostic to check the speed, an entire week has gone and nobody has contacted me as yet.