I own 3 decathlon bladders in the old style, the nozzle would regularly fall off with one lot for good. they would also leak slowly. new one's have a tighter fit and no leaks. they are also much cheaper than the old flawed design.
Bladder Bite Valve COVER
Used for 4 to 6 months
Please introduce a hydration bladder bite valve cover , otherwise the bladder gets very dirty to use.