gyro raw data goes crazy..... help!!!

hi everyone, I'm developing a project where take the raw data from gyroscope's mpu-6050, and I've correct the bias and show the data in my computer,
this is when I found an (I suppose) abnormal behavior while I was testing for measured angular velocity in the gyroscope

when I turned the board with respect to z-axis, it brings me good accuracy along +-360°, no problem

when I turned the board with respect to x-axis and y-axis, it brings me good accuracy along +-30°, but when I reach +-45° approximately, it begins to mark big values even when the board is steadily in this position, the measured values return to normal when the board rotate in the interval mentioned before

I would like to know if this is a normal behavior and if there's a way to deal with it, thanks