Header slowing down page load

Hi,

Since we’ve updated our webshop with more product images, attributes and descriptions the site has slowed down alot. I’ve been trying to work on on it and have most things up to speed with a caching plugin and by unloading js/css but i keep getting a very long initial load time. I’m not sure what this is causing but i do see a cancelled GET when doing a speedtest on GTMetrix, looking at the waterfall.
It’s refering to 3 similar of these headers:
wp-content/plugins/fami-buy-together/assets/vendors/fonts/glyphicons-halflings-regular.woff2
No matter if i have that plugin activated or deactivated it gives a loadtime of 4-7 seconds on them for some glyphicons that dont exist on the server anymore. Can anyone give me tips on how to find the thing pointing to that or disabling it somehow? Any help would be much appreciated.

King regards