Unable to "not-submit" a task with a particular condition (that is defined in Camunda Modeler)

I have created a Process-model (in camunda Modeler ) to do “Loan-approval” ,

I am trying to use the RestAPI to complete a task which is at Stage -2.

As per my understanding , the Camunda-engine must do a check of(feedback_submitted==true) , when I submit a task .

But , whenever I complete a task , it goes forward (for both the values true and false ) .

Hi @Arsh_Baghel
Please make sure in your XML view of your model that you have conditionExpression as sub-element of your sequence flow element. As in below example from camunda docs

<sequenceFlow id="flow" sourceRef="theStart" targetRef="theTask">
  <conditionExpression xsi:type="tFormalExpression">
    <![CDATA[${order.price > 100 && order.price < 250}]]>
  </conditionExpression>
</sequenceFlow>

https://docs.camunda.org/manual/7.8/reference/bpmn20/gateways/sequence-flow/#conditional-sequence-flow

I am using REST-APIs to complete the the business processes .
I always use " /task/{anId}/complete " to complete a task .

But , when I try to complete a task (of Stage 2 (in my BPM model ) ) without necessary conditions to go to the next task , it disappears from /task (list) and no next tasks (of stage 4 or 5) is visible.

So my question is " should I use /complete or /submit-form to complete a task ? " .