Retirement tax questions

It's 2021

I'm using TurboTax Deluxe

I'm in my sixth year of receiving OPM retirement

I know what my Total Employee Contributions are

Last year TurboTax calculated my taxable amount

It's not calculating it now.

It asked for my contributions and I entered it

At the end of INCOME SECTION it questioned a zero taxable amount for OPM!!!

Now what??