IF and Statement in Excel Power Query

You will have to add another custome column in Powerqueryas following,
= if [Type] <> null and [Type] <> "" then [Type]
else if [Amount C] <> 0 or [Amount C] <> null then "Renewed"
else if ([Amount B] = 0 or [Amount B] = null) and ([Amount C] = 0 or [Amount C] = null) then ""
else "Expiring"

Please accept it as solution if works.

I think this should do the trick. Add a new custom column with the following code:

if [Amount_A] = null then
    if [Amount_C] = null or [Amount_C] = 0 then
        if [Amount_B] = 0 or [Amount_B] = null

              then null
              else "Expiring"
       else "Renewed"
else [Type]


Tip: Basing logic on the False premise (C <> 0) often makes things more complicated. Try to build your logical from the true (C = 0) premise