This happens to my [ageing] 60/40/30/20 linked dipole - in the field - from time to time. The UltraLite wire breaks off right at the solder joint on one of the croc-clips used to make the links. I effect a temporary repair by using my teeth as wire strippers so I can stick the bare wire in the other croc-clip. I’m taking that linked dipole tomorrow, so fingers crossed.