Theoretically it won't solve. I'm going slightly technical, see if you can understand. For the floor water proofing to work, normally the waterproofing need to be apply on the flooring + extended slightly to the perimeter walls, usually 50mm to 100mm. The reason for the extension is to create a small "pond like barrier" to prevent the water from seeping through the perimeter walls. This finishes is only possible to be installed at the affected floor. If you apply the water proof at the floor below ceiling, the extension of the water proofing to the perimeter walls are not possible & the water proof layer will be 1 flat surface on the ceiling - the water will seeps at the perimeter walls & the new spot of leakages will be created.

This water proofing finishes extension slightly up vertically to the perimeter walls, is a very common missed out even in the construction industry.