Would appreciate some help with a very simple flow logic

[ikoalosaurus]

I have two SharePoint lists. Let's call them List A and List B.

List A has 10 columns. Default ID column and 9 custom columns (single field & choice mostly).

List B has 20 columns. Out of those 20 columns, there are 5 columns that are exactly the same columns from the List A. Those 5 columns are not in the form, because the idea would be that the flow feeds values of those 5 columns from the List A into List B.

My scenario is following:

Whenever someone adds a new item to the List B, the first column (number) they fill out is "Enter your ID". They are supposed to enter the value of the default ID column on the List A.

Once they fill out the rest of the columns, the flow is supposed to fill out the values from those 5 same that both lists are sharing, from the List A into the List B, based on matched ID of an entry.

I tried doing this on my own, but i ended up in a loop. I researched a bit and i see i might have to use special trigger in "When an item is created", but i don't know the syntax.

Could someone assist me with required steps in the flow ? :)

[#2]

Anyone? : )

[#3]

@ikoalosaurus ,

If my understanding is correct. You can write one event based flow which will trigger when Item get added into LIST B. 

1. Use REST API Action to find out ID In List A 

2. If you get Value in LIst A then Just copy those 4 values in current Item of LIST B.

3. If you did get value in List A then you can decide to delete current item from List B or Keep it with blank 4 values.

Let me know if you have any questions further on this.

-Shivaji