❔ WPF DataGrid

Hello everyone, I have a WPF application that has been giving me a headache. More than 90% of the work is done, but this DataGrid keeps refusing to behave the way I want. Most likely due to a lack of familiarity with the WPF technology - I hope that's the only reason. So, I've come here to ask for your help. I managed to center-align the headers of my DataGrid, but when I try to do the same for the data within the columns, the table cells end up completely misaligned. Although the data appears centered in the display, the cells are absolutely wrong.