Can a reply to an ongoing email conversation land in spam? - eviltoast

Had an exchange of emails with someone, around 4-5 back and forth emails. He then told me that my last reply never arrived. When I forwarded that email again to him, he told me that actually the original reply arrived but landed in spam… he checked it after I forwarded the initial reply.

It’s not critical or even a super important conversation but I think he lied to me. Is there any chance that a reply lands in spam if the last 4 mails in a thread arrived without a problem?

The emails were sent from a custom domain, using Office 365 Business. I have that email address for more than 6 years and I never had a problem with my emails landing in spam or never arriving. It’s the first time I am hearing about it but I think he is duping me.

Edit Thanks all for the replies, it’s good to know that it can happen.