For users who are trying to whitelabel email and are hosted through Squarespace you will need to modify the settings provided by Spiro for email white labeling to work.
Spiro will generate records for the "Name" that contain your domain name to add to your DNS. You will however need to remove your domain name when you paste the settings in Squarespace
For example Spiro will generate 3 records that need added (2 TXT and 1 CNAME)
What is Generated:
TXT
k1.domainkey.sp".mydomain.com"
TXT
sp".mydomain.com"
CNAME
email.sp".mydomain.com"
What you actually need to add to your Squarespace DNS:
TXT
k1.domainkey.sp
TXT
sp
CNAME
email.sp
NOTE: these entries above DO NOT contain your domain name - this is the correct way that Squarespace requires these records to be added. The "Value" added to Squarespace will be the same as displayed in Spiro.