Email to="" strange problem

There is a strange problem when using to=””.
When i use to=”[email protected]” the contact form details arrive to that mail but when i use to=”[email protected]” and which is registered using the gmail app for business then the contact form details do not arrive.

Anyone knows how to solve this?

Thanks in advance.

https://www.ads-software.com/extend/plugins/grunion-contact-form/