A simple replace of text isn’t working. I’ve reduced it to a simple text case. I’ve tested the regex manually.
Step 1: Tools module sets variable “First Name” to “Jean.”

Step 2: Airtable Get a Record module retrieves the record containing the text I want to modify.

Step 3: Tools module runs a replace on a field in the Airtable record. I tested the regex by hand and with a Web site.
I want to replace “{{First Name}}” with the value in a Make “First Name” field:

But the text isn’t replaced:

Please embarrass me by pointing out the simple mistake I must be making! With deepest gratitude…