How the plate is scored
MH12AB3456
Digits are taken in the order they appear and added. The total is reduced by repeated digit sums with master numbers not kept, so the plate always lands on 1 to 9, or on 0 if every digit was 0. The mulank is reduce of the birth day with masters kept, which is why 29 remains 11.
Harmony comes from the frozen friend table in the Solulu engine. Identical roots score 10, a mutual friendship scores 8, a one-way friendship scores 5, and neither scores 2. The published score is that harmony times 8, so the range is 16 to 80. The page prints the reduced plate, the mulank, and the harmony, not only the final number.
People check a plate before they buy the car. The habit is Indian numerology, not the RTO. This page does the arithmetic in the open. Letters on the plate are ignored. MH12AB3456 contributes 1, 2, 3, 4, 5 and 6. Those sum to 21, and 21 reduces to 3. Leading zeros would not change a sum. A plate with no digits at all is rejected.
Your side of the pair is the mulank, also called the driver number: the day of the month, reduced. The 29th stays 11, because 11 is a master number and this reduction keeps masters. The 14th is 5. The score then asks how those two numbers sit together in the planetary friend table Solulu already uses: 1 Sun, 2 Moon, 3 Jupiter, 4 Rahu, 5 Mercury, 6 Venus, 7 Ketu, 8 Saturn, 9 Mars. A friendly pair scores higher. The table is one published convention. Sources disagree on several pairs, especially anything involving 4, 7 and 8, and the page says so.
A high score is not permission to buy, and a low score is not a warning from the law. It is a numerology comparison of two reduced numbers. The name-correction tool on Solulu is the sibling for this one, because both are about a number you can still choose.