Match Column formula not working as expected

I am wanting two match to columns with the same data references (mostly), and then apply a filter from smallest to largest but its not working as expected.

EG:

if i have the reference A1 in cell B1, but the same reference A1 in cell D8, i used the formula - =MATCH(B:B,D:D,0) in column C to tell me what cell number the A1 reference was in in column D. then i added a filter and sorted smallest to largest.

its works in part, but once it gets past cell 20 - it goes awry?

any help appriciated - file attached