Amazon is showing my product star rating to be less than the average of my reviews

Hello.

I have never experienced this before, but when checking some of my products while searching Amazon to see where my products are showing in search results, I noticed my product star ratings were lower than before.

Product here: https://www.amazon.co.uk/Beddoes-Products-Marley-Redland-Forticrete/dp/B01BAOEQZO/ref=cm_cr_arp_d_product_top?ie=UTF8

Despite having 4 x 5 star reviews on one product, my product star rating is showing as 3.7 stars with 2 x 2 star ratings.

When I click to see these 2 star ratings/reviews, there is nothing.

I fear this is harming my sales by appearing of lower quality to potential customers.

I have sent a message to support but there is no reply.

Does anyone know what I can do about this?

Thanks.