What caused the weakening of the Abulkhair Khanate.

In the years 1456-1457, the khan was defeated by the troops of the Oirats, which caused the fall of his authority and the growth of discontent among the population. In addition, these defeats became the reason that part of the Kazakh population migrated to Moghulistan, headed by the khans Kerey and Zhanibek. Nevertheless, Khan Abulkhair decided to punish the apostates and went to war against them. But during the campaign, he dies. Thus, the power of the Abulkhair dynasty in Central Asia ceased.