Why did three voting rights laws president Johnson put into affect fail?

President Lyndon signed a right voting act that gave the African American opportunity to participate in voting. However, the bill did not push through but made illegal restrictions, and as a result of this, the votes of the blacks were declined.

Prior to Kennedy's assassination, Johnson assumed the power as the president but later, he was elected. Even though Johnson became the president, Africans did not have freedom of voting, they were forced to take literacy tests upon the ballot, and they failed; besides they encountered small challenges that they prevented them from voting.