BMW E39 540i 2001 Loss power and long cranking after getting warm

Hello Guys I have bmw e39 540i 2001, the problem happened this summer and till now its happening.
the problem is cranking and loss power.

usually in the morning the car start normal and run fine after it get the normal temper it begins to decrease it power and sometimes when I turn it off and then on it has a long crank then I turn in it on and then on the same thing, the third time it will turned on and have a sound (tuk).