Extract Text characters only from a cell

Hi All,

This is very similar to my previous post, which was solved. Now that I've extract the numbers, I need to extract the text for the specific work activities, for example 13Z or 9GGG. I'm assuming some variation on this formula:

=LOOKUP(9.99E+307,--MID(C4,MIN(FIND({1,2,3,4,5,6,7,8,9,0},C4&1234567890)),ROW(INDIRECT("1:"&LEN(C4)))))

is the solution, but I'm struggling with making the correct alterations.

Thanks in advance!