why did rajkumar shukla invite gandhiji to champaran? How did gandhiji solved the problem of indigo farmers?

Raj Kumar Shukla was a representative peasant in the region of Champaran where the matter of the sharecropping system had become a huge trouble for him and his fellow croppers. The poor farmers were compelled to cultivate indigo on 15%  of the total farm lands of Champaran and deposit the entire harvest as a sum of their rent to the Britishers which they apparently owed. Raj Kumar Shukla had heard from somebody that Gandhiji, being a knowledgeable advocate could be of help to them regarding this issue, and so Shukla approached him in the city of Lucknow.

Gandhiji, helped and supported the peasants in securing their rights, by officially taking up their case in the court as he himself was an advocate. In spite of constant discouragement and getting bullied every now and then, he stood stern by his stand and fought to resolve the issue in favour of the farmers.