Domain wiped out hosted email

Hi. My domain is hosted outside of Squarespace. When I followed the instructions laid out in the generic "how to update your domain" guide found here https://support.squarespace.com/hc/en-us/articles/205812378 and updated the DNS records on my site to the ones in the guide, it completely wiped out my email. I had to spend hours with my site host restoring email. I don't use godaddy. I am not interested in transferring my domain to SS, as I have several other domains through my host and prefer to keep it there. I did not delete any MX records from the DNS so it should not have affected anything else.