There's a few threads on here that discuss this issue and how to deal with it. Just do a search and you'll find them... just as fast for you to do that as it is for me to do it and provide the link for you.
If you feel around at the boom of the fabric you will feel it has a plastic strip. Take the plastic strip and flip it around the metal frame of the top and make sure it makes a click noise when pushed in. It’s very tight so don’t just tuck it and think you are done.
Sorry about the response above meant to read bottom not boom?! Really need to keep an eye on that autocorrect or just start spelling better! I feel it makes up words sometimes as of late, maybe an update including predictive text?
I feel your pain as I have the same problem. No harm in giving mtnghost suggestion a go but in my experience it wont be a permanent solution as its a known problem caused by too much tension on the inner lining. Mazda issued a service bulletin (attached) to its dealerships that included detailed instructions on the use of 2 plastic clips and glue/resin. Sadly as seems to be case on all things 124, Fiat dealerships in the UK have never heard of it (Arnold Clark my supplying dealer had 2 goes at simply gluing it before I lost patience). The process is fiddly and so far Ive resorted to mtnghosts instruction every time I lower the roof and put it back up but I'm going to take my car to Mazda to see if they will be willing to give it the serice bulletin instructions a go on a 124, The problem is supposed to mainly affect earlier cars, so its likely the technicians will not have any/much recent experience of the fix.
You were right!
Carefully feeling both edges that were hanging down, one attached to rear window side and the other attached to the roof, I ran my fingers along both edges. I didn’t feel a tear or any rough edges indicating a break. It simply came apart.
Carefully looking at the top portion I could faintly see a crease in the fabric. Ah, this must have been folded upwards. Folding the roof portion up, then backwards, like towards the front of the car, I slowly thread into the slot on the strip that is attached to the rear hanging piece. I felt it go into the slot. Then slowly, almost imperceptibly, began working from the center of the window to the end. Once I got to the end I heard a “Click”.
Still firmly grasping the center portion I had started at, I switched hands and began once again threading the slot in the other direction.
It’s a hot day in Houston, the air is thick with humidity and the car is in the garage making it feel hotter. I’m 60yrs old and my physique still hasn’t shrunk down much from all the years spent at the gym. At 6ft and 260lbs the strain was getting to me.
I slowly threaded the two pieces together, like closing a ziplock bag. Concentrating, the beads of sweat were now running down my face. Almost..almost.. one more inch, it was like defusing a bomb. Should I stop and tell my wife it couldn’t be fixed? No. Reach the end or die trying. Then … “Click!” Success, It was attached.
Thanks again for your help and consideration! Tonight there will be a celebration.