Not showing gravatar configured image

Hello, i am using plugin latest version.
I configured Ultimate Member to use wavatar image. Problem is, wavatar is showing for everyone who has also a gravatar configured image. Wavatar should be apply who have no gravatar configured image.
I tried all gravatar option. After all, there is no setting to use gravatar configured image.
This is disgusting. How to fix this?

https://www.ads-software.com/plugins/ultimate-member/