Hi @deepikarama,

You can resolve this by creating the missing system property manually. These limits are controlled through system properties, and if a property is not present by default, it can simply be added. 

Please create a new system property with the following details: 

• Name: sn_flow_designer.max_action_vars 

• Value: Set this to the number of inputs you require (for example, 25). 

Once created, the updated limit will apply, and you should be able to add more inputs to your custom action.
 

For reference, a similar discussion can be found here: I can't find "sn_flow_designer.max_action_vars" and "sn_flow_designer.max_script_variables" .

Thanks & Regards, 
Muhammad Iftikhar 
 
If my response helped, please mark it as the accepted solution so others can benefit as well.