Your new record in KPI's is not yet linked to any record in Client Info and thus set field can't "get there" to the correct client info record in order to set your Client ID field to the needed value. Once you have that link, you no longer need this set field step.
And getField is the wrong function to use here as well.
Do it this way:
Set Variable [$ID ; value: Client Info::PK Client ID ]
Go to Layout ["KPI's" (KPI's)]
Set Field [KPI's::Client ID; $ID]
So you are saying to use that script until I fix the relationship issues and make sure those tables are connected.
No. your relationship is fine. You just need to use this script.
It worked! Thanks!