Why are there 2 different genealogies in gospels of Matthew tax collecter & Luke physician?

Likely Matthew wrote 1st record to link Messiah to the promise of Kingship of Jerusalem given to Abraham & passed down through David,
Solomon & Kings of 1st temple bloodline of Solomon!

Notice though Matthew fudges the numbers of generations between David & being carried away to Babylon as 14 generations by omitting 2 or 3 kings!

People likely saw that & also questioned about how Salathiel & Zerubbabel could pass on kingship if bloodline cut off in Jeremiah 22!

Jeremiah 22 says bloodline of Jeconiah is cut off from continuing rule,
Matthew genealogy doesn't show it,
shows crown passed from Jeconiah to Salathiel/Zerubbabel to Joseph dad of Messiah!

Luke came to explain how crown/Kingship passed to Salathiel without bloodline continuing!

Luke shows Neri from bloodline of David's son Nathan is father of Salathiel/Zerubbabel,
so how could Jeconiah be too?

Deuteronomy has answer in 25:5-10!

If husband dies without children,
closest living relative is responsible to marry widow & have child as heir of dead husband!

Was important to show Salathiel is son of Neri & had bloodline of Nathan while being son of Jeconiah's widow that allows Salathiel to be heir to crown of Solomon through Jeconiah to Salathiel!

Luke could choose to recopy Matthew's genealogy after that point or give more info!

Luke decides to show Joseph's mother was married to Heli who is of Zerubbabel's bloodline & Heli died without child,
by showing Heli as legal father of Joseph as heir of Heli through Deuteronomy 25:5-10!

Joseph would have been heir to crown through both natural & legal fathers!