Purged site cache still returns deleted images

I have enable tiered caching on one of my Cloudflare sites with cache reserve active.

I had uploaded some advertising images and now after removing them from the wordpress site and purging all cache from Cloudflare I still occasionally see some of this images on my site.

Is there a way to validate that it’s caused by the cache or a way to be 100% sure that the Cloudflare cache is deleted?