We have distribution list forwarded to our HelpDesk for Onboarding/Offboarding forms. When HR sends those forms in they're merging into older requests automatically. The subject line is nearly the same for each ticket except the employees name differentiates it, eg; "Termination/Resignation - [First Last]" or "New Hire - [First Last]".
I ensured there was no triggers or rules to merge tickets together. We've also traced the e-mails in the O365 Admin center and they're sending properly, but something is causing them to merge into old tickets so the new requests are not getting visibility.