Lost Buy Box on ALL FBM products

Hi there, this morning I got 100’s of notifications from H10 saying I had lost the Buy Box on all our FBM listings, our FBA listings are okay but a lot of them we send out ourselves. Contacted Seller Support but just got an unhelpful copy and paste reply…has anyone ever experienced this before and can help?

Our account is in “good health”

We have inventory

We have good sales volume

We are the brand owner and only seller

I really can’t work out why we’ve lost the Buy Box or is it just a glitch that will sort itself out?

Any help greatly appreciated!!