It is possible at the time of submission of pacticular assignment. When you are using the autocomplete if the user enters the wrong data means it will not return any data but still the value is present in the field. At the time of submission it will through an error. Is it ok means I will show. Let me know first.
Thanks for your responce, i got the solution , i wrote activity and am calling that activity in section level.please find the below attached activity screen shot for your refrence any how share me your solution also.
The usage of the activities should be limited in the application because in the real time scenario it will degrade the performance. Rather calling activities I think we will do that in the flow action validate rule.