According to 1040 instructions,my wife passed in 2021 and I qualify as a Surviving Spouse but the online program says my filing status is Single. Why?

[VolvoGirl]

Do you have a child?  You can file a Joint return the year your spouse died. For the next two years following a husband's or wife's death, the surviving spouse can file as a qualifying widow or widower if they have a qualifying child. That basically lets you continue to use the same tax brackets that apply to married-filing-jointly returns. After the year of death if you don't have a child you file as Single.