It seems that in the past few months Google have been tightening up their controls over spam and unwanted/scam email. While this is a good thing as no one likes spam it does mean that you must train your Gmail account to tell it what is definitely not spam and what is.
You might find some of your mail addressed to your domain name hosted with Lemonberry is ending up in your spam folder. If you find valid mail in the spam folder it’s important you train Google and click the “Not Spam” button. Respectively if you find spam is creeping in to your inbox, tell Google it’s spam. If you’re still finding mails are getting in the wrong folder you might want to think about creating a filter.