Pack the gaps tightly until they are full and subsequently get rid of of any excess grout.
In addition, clean the bulbs and shades of one's light items. If the leak is from your own pipe deeper inside your walls, support to go out the main water valve for your property. https://Wiki.Insidertoday.org/index.php/How_To_Trade_A_Messy_Disorganized_And_Dated_Home_For_More_Money