Water on top shelf in regrigerator

I can’t afford a pricey visit for repairman. I have water pooling on top shelf of the refirgerator. It is frost-free. No ice maker installed. Freezer on top. I defrosted it and thought that may solve the problem. I put things back in my refrigerator, as it seemed okay. It started pulling water again.

I would like to attempt to fix this myself, if it is not too complicated. I thought that by defrosting it would have thawed any tubes/pipes frozen.

Thanks in advance for any replies.

Do you have a frozen sheet of ice like a lake on the bottom part of your freezer? Check the vent coming down from your freezer to the refrigerator part and see if you have ice inside there that’s melting downwards.