"match" (in CALC Version: (x64)) is not working right...

I am building a rather large and complex "design project management: (Calc) spreadsheet. The user selects a “Design Type” using a “validity” command. Elsewhere I use the “Match” command to get the “offset” from the validity’s “source text.” It does not always work.
image description
This is the "source for the “validity” and associated data.
image description
This is the “result” of my “match” and “offset” efforts.

The “Match” command is written as: “=MATCH(AMG6,$‘Operational Data’.$AMC$3:$AMC$13)” in my code. ???

Yes – I aman idiot! I left off the Exact Match 0 from my Match call. What mind???