That is not unusual. There are many reasons that could result in such a situation; and since this is a public forum you do not want to post your personal information.
Each income entry is processed as if it were the only income you had; thus until you enter ALL W-2s your input data is incomplete and hence incorrect.
Make sure you entered the information CORRECTLY and did not mis-type any numbers
The 'monitor' is only a guide (marketing hype). It is generally meaningless until you have entered ALL of your information since the calculations are inter-related.