CvC gets more points than clan influence for knowledge/build upgrades ... did you happen to destroy any buildings because that then takes away the influence that the building had built up ... you might not see that in cvc but clan influence event you can ... you can even have a negative score in clan influence event.  Also if you haven't tried it you might want to refresh your game.

No.  I destroyed no buildings in the process. Nothing was recorded in the Influence Increasing event. I expected about 65 million. CvC correctly recorded over 300 million. Further, refreshing the game as well as logging out and back in did not change anything.

My influence I reducing from 140,603 to 129,786 what should I do

Have you # been attacked?

               # attacked someone?

               # destroyed any buildings?

               # swopped Shaman?

Yes

Why would changing your Shaman changed your influence or reduce your influence score?

Your different shaman could and usually have different influence (the influence depends on their level).