Test email only sometimes works

Hi,

I installed the plugin and followed this guide for setup.

When using the test feature in the plugin it will only successfully send to certain address i.e. my own one but none of the groups i am part of. Which is what I want it to do as this will be the main enquiry form to go to the sales team.

Any suggestions?

https://ww.wp.xz.cn/plugins/gmail-smtp/