A Nontrivial Math Error in “Sophisticated Monetary Policies”

[1] is an important literature in the field of the fiscal theory of price level. However, I prove that the equations of (39) in [1] are wrong and provide the correct results. I also find that the mistake of equations of (39) affects the rest of [1], which is based on the establishment of equations of (39). I list all the results in [1] that cannot be established due to the mistake of equations of (39). Considering the importance of [1] in the field of fiscal theory of price level, all knowledge developed by far based on the results that cannot be established in [1] should be re-examined.