The reason some of those letter are rendering with a different font asset which is most likely LiberationSans SDF which is assigned in the TMP Settings as the default font asset, is because these characters did not fit in the atlas texture based on Generation Settings you defined.
Looking at the Generation Settings, the sampling point size of 90 is fine. However your padding value of 50 is most likely way too big. Typically, you want the Ratio of Sampling Point Size to Padding to be 10% where in this case, the padding should be 9.
To resolve this issue, reduce the padding to 9 and Apply.
I had set the padding to 50 because anything lower was giving an undesired Drop Shadow result. Changing it back to a value of 9, and setting the drop shadow’s Y value to max (-1), makes the drop shadow far smaller than desired.
Desired result:
Result with 9 padding:
There is seemingly no shadow here, even though the y offset value is at max (-1)
Result with 50 padding (desired look):
This results in a shadow far below the text, which is the desired look. Otherwise it is basically imperceptible.
The Ratio of Sampling Point Size to Padding is what determines the effective range of material properties such as Dilation, Outline, Underlay Offset, etc.
As per the above, if the sampling point size is 90 and the padding 9, the effective ranges of the underlay will be about 10%. If the padding is increased to 18 then the effective range will be doubled.
Increasing the padding means each glyph takes more space in the atlas texture where in your original font asset with an atlas size of 1024 x 1024, it was not possible to fit all glyphs.
The solution would be to either reduce the sampling point size while maintaining the same ratio. This would affect the sampling quality of the glyphs but would allow you to fit more. Or increasing the atlas size to 2048 x 2048 which would allow you to fit more characters. You could also enable multi atlas texture while using a 1024 x 1024 as well.
Regardless of the sampling point size to padding ratio, it is always best to avoid using material property values at their max as this can result in visual artifacts.
See the following video which does explain the multi atlas texture feature.