Translation:It took two weeks.
To clarify this I brought it to HiNative. One of the best answer might have proved me wrong.
It said that the use here (as an adverb I reckon) should not have the character 間. So these are correct:
Nevertheless for week it has been a habit to say with 間, so usually
albeit less common, should not be considered as wrong.
It also said that misuse such as 三年間かかります is not rare in Japan. The provider thought it may be due to confusion with the form in 三年間でかかる(費用など)/(expense etc.) incurred over a period of 3 years.