Here is the auto generated code from PE with KSDK for KL46
OSA_InstallIntHandler(I2C0_IRQn, i2cCom1_IRQHandler);
I2C_DRV_MasterInit(FSL_I2CCOM1, &i2cCom1_MasterState);
I2C_DRV_MasterSetBaudRate(FSL_I2CCOM1, &i2cCom1_MasterConfig0);
NVIC_SetPriority(I2C0_IRQn, 64U);
the problem is in NVIC_SetPriority(); the function do the bit left move for priority, so the 64 should be 1 or 0x01