Look after your zips cause any damage to them would require new zips installation , which is in most situations rather expensive operation. Here we have some tips for keeping zips in good condition .
Never force zips. If they will not slide with ease, lubricate, backtrack and try gently again.
In Tents zips - Lubricate full zip length regularly with a pure SILICON SPRAY.
Never use oil based lubricant as it attracts grit and will therefore wear out your slider at a fast rate.
Keep zips clean (use a tooth brush to remove any dried mud)
If the lock comes hard it must be greased on both sides candle and move the slider a few times on zip tape
To improve the operation of the zip can also use a soft pencil. Grease the zip on both sides of a pencil, and then move the slider several timeson zip tape
If the lock comes hard it must be greased on both sides soap and move the slider a few times on zip tape
If the broken zip is made of metal then we can try to fix the slider, using a pliers. Squeezing pliers slider on the tape , than to move slider up and down to see if a better moves, if that does not work, we unfortunately have to replace the slider....