Email Not Being Received (Admin)

Hi,

Does anyone have any ideas as to why when I send a test submission via this plugin the following happens:

1) Submitter (i.e. user) receives a confirmation email
2) Admin (i.e. me) does not?

Also to expand further I have tried this plugin with other email addresses and it is working 100% ok, but still not with this individual email address.

Any ideas? Would really appreciate some help as this is the same/main domain email address for the business.

cmhardi1

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