Formula Rich Text -> test conditioned by Related link

Hello,

I would like to create an app with 2 main functions:
1. Request Price
2. Answer to price request.

You will see my app structure on picture "Capture.PNG".
You will see the interface of "Request Price Form" on picture "Capture1.PNG".
You will see the interface of "Sourcing Answer Form" on picture "Capture2.PNG".
You have the list of all filed of "Request Price" table on picture "Capture3.PNG".

In a nutshell, I would like to setup the "Status" field from table "Request Price" to change the status automatically to "Completed" once there is at least one "Sourcing Answer" Submitted for this specific price request.

I tried to do it myself by using Formula Rich Text field with the following code but it does not work (picture "Capture4.PNG"):
If(IsNull([Sourcing answers]), "Pending", "Complete")

But it does not work as it show alaws "Complexe" even when there is not sourcing answer done for the Sourcing request (picture "Capture5.PNG").
Your help will be greatly appreciated. Thank you in advance.

Anthony

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Anthony Charrieu
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