It is just too hard to tell what is wrong exactly. Maybe add yourself as a BCC to each email so you get a copy and can see if a bunch are going out at any given time to give you something to investigate. Without knowing the page or reason that the emails are being sent it is really difficult to fix.
Shared hosts should track which client sends the email.
I think if you own Data Bridge v2 you might try using the authenticated email option that you can set up to use your regular email account and that might bypass any email limits.
Did this help? Tips are appreciated...
