If your consultation email is sending the literal word null in the body of the message, the cause is almost always an empty Event Description field on the consultation.
What's happening
The consultation email template pulls your Event Description (sometimes just labeled Description) into the body of the email. When that field is left blank, the template renders the word "null" in the spot where your description would normally appear.
How to fix it
Open the consultation in SynkedUP — either from the customer's profile, or directly from Scheduling.
Scroll to Event Description.
Type in a description. If you don't have anything specific to say, a generic line works fine — for example: "We look forward to meeting with you."
Save the consultation.
Resend the email — the body will now show your description instead of "null."
Quick tip
If you regularly send consultations without much custom text, just keep a short generic phrase in the Event Description so the email never goes out empty.