Leak through the roof vent.
Plastic conservatory roof leaking.
The fowong butyl tape works to repair cracked roofs across multiple surfaces including metal fibreglass wood textile plastic aluminium and more.
Thoroughly clean the area and fit specialist htg adhesive flashing to bridge the problem area.
Our advice would be to get a conservatory roof specialist to visit and check out the scope of the repair work.
For what it counts and based on your initial message you may not need to replace the polycarbonate just the rubber seals and maybe underside spacer strips if any.
A conservatory roof leaking in centre could be due to a slipped or incorrectly fitted roof panel a cracked glazing unit or a perished seal.