Who installed the battery? Was it coded? Your car has a "smart" alternator that charges based on the age of the battery. If it's not coded, it can screw things up and quickly ruin a new battery. What is meant by "coded", is that the car must be told that a new battery was installed, and what the CCA of the new battery is; as correct batteries for this car can vary a bit in CCA.
Go to an autoparts store and get a battery terminal brush. This has two ends; a female wire brush that fits over the terminal post, and a male end that fits inside the battery cable clamp. Remove the cable, clean both ends and reinstall. Ideally, hook up a battery saver device or jump pack to the car while the battery cable is disconnected so you don't lose you personalized settings. If you have white corrosion around the terminal, this can be neutralized with a combination of baking soda and water.
Once both things are done, if it does not clear up your problems, you need to start looking for other issues. Next step is to get both the battery and alternator tested by someone who has a sophisticated battery / electrical system tester; like a Snap-on EECS750:
https://store.snapon.com/Electronic-...m-P823717.aspx
Confirm that the battery is still good, and the alternator is charging properly. Often a failing alternator will be working, but just not putting out the correct voltages all the time. These tests must be done by someone who is familiar with these cars. This is NOT like a car from your youth where an alternator could be tested by removing a battery cable while the car is running to see if the car stalls....we're in a whole new world of sophistication with an X5; or any modern BMW for that matter. Either an improperly charging alternator or a battery that's not holding its charge can cause a low voltage situation that will cause all sorts of wacky issues in an X5. The fact that you've had to jump the car on multiple occasions is NOT a good thing. Every time a battery gets run down to the point that you need a jump, it never comes completely back (unless it's a marine type battery).