More efficient US state codes Abbreviate that US state! was fun, but we learnt that efficiently abbreviating US state names is hard with the current system. Let's come up with an alternative state code scheme for efficient golfing.
Your task:

Write a function (or program) which, given a valid US state name (only the 50 normal states required), returns a unique two-letter code in uppercase identifying it. The code must meet these requirements:

The first letter must be the same as the first letter of the state.
The second letter must be one of the other letters of the state (not a space).
It must always give the same output for the same input, and must never give the same output for two different valid inputs.


For instance, given &quot;Alabama&quot;, your function could return &quot;AL&quot;, &quot;AA&quot;, &quot;AB&quot; or &quot;AM&quot; - as long as it doesn't return that value for any of Alaska, Arkansas, etc. (&quot;AA&quot; is only possible because &quot;A&quot; appears more than once in the state name.)
Standard loopholes forbidden. Standard input/output are ok. This is code golf, so shortest solution, in bytes, wins.
The complete list of possible inputs is here:
Alabama
Alaska
Arizona
Arkansas
California
Colorado
Connecticut
Delaware
Florida
Georgia
Hawaii
Idaho
Illinois
Indiana
Iowa
Kansas
Kentucky
Louisiana
Maine
Maryland
Massachusetts
Michigan
Minnesota
Mississippi
Missouri
Montana
Nebraska
Nevada
New Hampshire
New Jersey
New Mexico
New York
North Carolina
North Dakota
Ohio
Oklahoma
Oregon
Pennsylvania
Rhode Island
South Carolina
South Dakota
Tennessee
Texas
Utah
Vermont
Virginia
Washington
West Virginia
Wisconsin
Wyoming
Jelly, &nbsp;13&nbsp; 12 bytes

907ị;⁸Qḣ2ṢŒu


A monadic link taking and returning lists of characters.

Try it online! or see a test suite

How?

907ị;⁸Qḣ2ṢŒu - Monadic link: list of characters, state    e.g. Alabama   or   Kansas
907          - literal 907
   ị         - index into state                                b              K
     ⁸       - link's left argument, state
    ;        - concatenate                                     bAlabama       KKansas
      Q      - de-duplicate (unique by 1st appearance)         bAlam          Kans
       ḣ2    - head to index 2                                 bA             Ka
         Ṣ   - sort                                            Ab             Ka
          Œu - convert to uppercase                            AB             KA


Indexing in Jelly is 1-indexed and modular, so the 907th index of something of length L is the (907-modulo-L)th item. For example for "Alabama" the length is 7 so the item at index 907 is the (907-modulo-7)th, and 907-modulo-7 is 4 (907 = 129 * 7 + 4), so the item at index 907 is 'b'.

907 is the first positive index at which the state abbreviations using index 1 and that index over all of the 50 states become unique.

State names, including their spaces, are of length 4 through 14 inclusive, and 907-modulo-6 is 1 (whereas for all other lengths the value is not 1). This means that if we were to use the 1st and 907th characters for the abbreviations that Alaska, Hawaii, Kansas, Nevada, and Oregon would be AA, HH, KK, NN, and OO respectively - this is not acceptable for Hawaii, Kansas, or Nevada; so an adjustment needs to be made; this is the reason for the concatenation, de-duplication, head to index 2 and sort, this makes Alaska, Hawaii, Kansas, Nevada, and Oregon become AL, HA, KA, NA and OR respectively and does not collide with existing state abbreviations.