When SOS Inventory sends the email and lists your email as the from email address, it can sometimes trigger a filter that regards the email as spam.
Please go to lookup.icann.org/en to discover the service that hosts your email. Then, go to mail-tester.com/spf/ to find instructions on how to add a TXT line to your SPF record for your domain. The TXT to enter is v=spf1 include:mg.sosinventory.com ~all
This text allows the SOS Inventory system to send emails on your behalf without them failing the SPF filter.