God's Word is perfect and cannot contradict itself; therefore, whenever we see two or more passages of Scripture that appear to contradict each other, we need to study the passages in more detail. We must make sure we are examining the same event, do not take words out of context, recognize any figures of speech or poetic language being used, and be aware of any translational issues of words or phrases, from the Hebrew, Aramaic, or Greek into English. Let's compare the three accounts of the healing of Jairus' daughter in each Gospel.
While He spoke these things to them, behold, a ruler came and worshiped Him, saying, "My daughter has just died, but come and lay Your hand on her and she will live." (Matthew 9:18)