Regular Lag Spikes

Hi there I have been having this issue for awhile now and was wondering if there is anything I can do to fix it?
Basically while playing FFXIV I get 5 second lag spikes every 10 or so minutes, Its not game braking but can sometimes wipe my raid due to me sitting there not doing anything until the connection regains and is quite frankly just annoying.
I have Sky Fibre and when I perform a net test I get 37 down, 8 up and 6ping and when its not spiking it performs fine, I just feel that I get way too many spikes.
Any way to fix this?

Thank you