Please follow the below Google support link to create a filter and to avoid getting website notification emails in Spam Folder.
Otherwise, follow the below steps.
Login to your gmail account and note the subject “[Ultimate Irish Dreams Advertising] - [ Reservation Form]” of your notification emails from your website.
Click on the link “Create filter with this search” link in the bottom corner of the search box.
Click “OK”. If you get this kind of alert.
Check the option “Never send it to Spam” in the search box and Click on “Create Filter” button.
Check the “Apply the label” and create new folder or select the existing folder that you want to move the mails.
Now the notification emails are moved to particular folder/inbox with the specified label and not to be moved to Spam folder.