Step 1:
You can go to a client profile that has the booking section and click the gear icon next to the title
OR
Go to more-> profile builder and click the pencil icon of the booking section
Step 2:
Click add field

Step 3:
Select to add a preset section

Step 4:
Select recurring fields

Step 5:
You can edit the label and if you want to add a description you can a field remark by selecting other properties and then field remark

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