So I have a test coming up on friday and I'm having this issue when attempting chi-square test.

I enter values into matrices A and B for my tables
I go to stat section and compute chi-square
My calculator gives my incorrect value for chi square and p-value
Upon checking matrix B I see that the values have been changed.

I've reset the memory and restored settings, but I continue to have this issue. Please help!

The chi square test for independence computes the correct expected values and stores them into [B] (or the matrix you selected). You shouldn't need to put any values into [B]. I don't know what could be going wrong.

If you want to to test for goodness-of-fit, you need to use X²GOF-Test.