Hello @Wixcart, User optimized size images for your store. It is main issue in your site
These two images are very heavy. Remove these image in your store. Please use less than 150KB sized images.
If it is useful mark this like and accept solution
The total page size of your product pages are huge. I suggest you use gtmetrix.com to see what exactly is slowing it down.
Like what was suggested earlier, the product images uploaded are an enormous size. Your reviews app also can be improved so I suggest you reach out to the app developer and notify them that they have no compression on all their files.
First, I would check https://www.shopifystatus.com/ if Shopify have any issues. If all is green, check if you didn't install any new large apps recently. They can be a reason for slow loading time on your store. You can hide slow loading behind some page animation. There are apps for that, for example https://apps.shopify.com/preloader You can also hire developer like myself, to take a look into your store and let you know what is going on there.