Your transmission is malformed, containing 31 bytes of payload data (PDU length of 37) when its internal length fields indicate it should in total contain only 30 bytes (PDU length 36).
Let's take a look at your data
02 01 1a
This is a length (2) of type codes - 01 and 1a, and good so far
1a ff 4c ...
Now we have a problem - the 1a is a length code for this field (manufacturer specific data), value of 26. Yet 27 bytes of data follow it in your case, instead of the proper 26 you have indicated you will provide.
Now, if you have a properly formed packet, you will still get a larger buffer padded with meaningless (likely uninitialized) values following the proper content, but you can simply ignore that by parsing the buffer in accordance with the field-length values and ignoring anything not accounted for in the proclaimed lengths.
But with your current malformed packet, the copying of packet data to the buffer stops at the proclaimed content size, and the unannounced extra byte never makes it into the buffer your program receives - so you see instead something random there, as with the rest of the unused length.
Probably, when you made up your all-zeroes "region UUID" (might want to rethink that) you simply typed an extra byte...