Awning zip help please

I have an Issabella awning with a tall annex. The awning side zip end metal piece (the bit that mates with the opposite bit on the side wall) has become dislodged, leaving just material and the first zip element. I have attempted to refix without success.(Only limited tools) Can anyone advise how I might refix the metal end. Otherwise the zip works perfectly well. I can get the zip replaced but it does seem a bit of a job for what might be a simple solution.