that I saw in a pdf document. However, when I google the mathematical alphanumerical symbols on Wikipedia, it has symbol styles for other letters, but I seems to be reserved.
Some of the omitted symbols here were thought to have already appeared earlier in Unicode. Your Wikipedia table says in a note
The reserved code points (the "holes") in the alphabetic ranges up to U+1D551 duplicate characters in the Letterlike Symbols block
U+2110 is "Script Capital I" and looks like ℐ allowing
U+1D4A4 to be ignored
U+210E is "Planck Constant" and looks like ℎ allowing
U+1D455 to be ignored