Make sure that nothing has dropped into the gap between the ridge and the roofing material. If so then clear it out. Kew offered good advice to deal with raising the rubber seal, which can be a problem without access equipment.
Once all is clear you should be able to carefully push the glazing back towards the ridge.
If you want a long term solution to your slipped conservatory roof panels then take a look at an end cap replacement kit. Just google "end cap replacement kit" - Truly Conservatory Repairs sell two types of these kits through eBay, so you could save money by doing the job yourself. The kit has a strong aluminium retainer, so shouldn't drop again! Good Luck :-)
bflyfloat
August 2010