Struggling to work out why python complaining at line 4:

```
import sys
import re
problem = input("What is wrong with your mobile device?").lower
water = re.search(r'water', problem)
screen = re.search(r'screen', problem)+ re.search(r'smashed',problem)or re.search(r'cracked',problem)+ re.search(r'display',problem)
software=re.search(r'software',problem)+ re.search(r'program',problem)
keypad=re.search(r'keypad',problem)+ re.search(r'keyboard',problem)+ re.search(r'text',problem)
speakers=re.search(r'sound',problem)+ re.search(r"can't here",problem)+ re.search(r'cant hear',problem)
microphone=re.search(r'microphone',problem)+ re.search(r'cant hear me',problem)+ re.search(r"can't hear me",problem)
battery=re.search(r'battery',problem)+ re.search(r'swollen',problem)
charger=re.search(r'Charger',problem)+ re.search(r'charge',problem)+ re.search(r'charging',problem)
if water:
    print("If your phone has suffered water dammage there is not much you can do, it is recomended that you buy a new phone")
    sys.exit
elif screen:
    print("If your screen is cracked then it is recomended that you get it repaired this is not too expensive.")
    sys.exit
elif software:
    print("If you have a software issue then contact the product manurfacture, they are the only ones qualified to fix this.")
    sys.exit
elif keypad:
    print("Clean your keypad with a wetwipe, do not get the charger port or jack port wet.")
    sys.exit
elif microphone:
    print("Your microphone hole may be blocked, please clean this with a soft dry tooth brush, if this does not work then please retern the hand held device to its manufactures.")
    sys.exit
elif battery:
    print("If your battery is enlarged/swollen you have probbaly over charged it it is recomended that you buy a ned battery.")
    sys.exit
elif speakers:
    print("The speaker on most phone is located on the side or back or the device if this is blocked then please attemt to clean this with a dry, soft toothbrush, if this does not work please contact the product manurfacture.")
    sys.exit
elif charger:
    print("If you have not tryed buying a new charger then try that. If a new charger does not work, please send your mobile device to the product manurfacture.")
    sys.exit
else:
    print("please write your problem again, attempt to use keywords that relate to your problem.")
    sys.exit

```

If someone could tell me how to correct this or correct this themselves it would be much appreciated.