Output not visible in excel

Question

I have tried to insert empty rows in excel sheet using openpyxl though my code is being completely run in python when I see my workbook only some part is executed and the rest is not printed while python is showing whole code is being executed

code :

count = df['VAR_NAME'].value_counts(sort = False).values
val =21 -  df['VAR_NAME'].value_counts(sort = False).values
ctr = 0
i=4
j=0
while(i<20000):
    if(ctr == 436):
        break
    ws.insert_rows(i,val[ctr])
    i += 21 - count[ctr] + count[ctr + 1]
    print(i)
    j=j+1
    print(f"J={j}  ctr={ctr}  I={i}")
    ctr=ctr+1

the output is showing the whole loop is being executed