Puddles in the back right rear passenger floor

I have a 2006 Jetta TDI and when it rains s puddle forms in the back right passenger floor. Anyone else have this problem and know what it is or how to fix it?

If you have a sunroof the drains are probably clogged. There are threads here already about how to clear them. Some use small diameter string trimmer line to snake down from the sunroof to clear them. But be careful and don't use any force as it is easy to get the tubes to disconnect from the fittings and you will then have a worse issue with water. Search and read the threads here and you should be able to do it.