All babies come in different shapes and sizes. You may find that one brand of cloth nappy may fit your bub better than others. Some babies are also more heavy-wetting than others. To help you troubleshoot nappy leaks, here is a short guide on why they may be leaking and some recommendations on how to fix it.
Make sure that the fit is snug around the legs. If there is a gap in the legs, you will get leaks. Same with the waist and the back of the nappy - adjust the rise setting accordingly. A lot of leaks occur due to the nappy not being tight enough. If you have a boy, make sure that his private part is pointing downwards.
Also make sure that all fabric material/ inserts are tucked in and only the waterproof layer of your nappy is exposed.
The fabrics of your inserts have different levels of absorption. Microfibre, absorbs very fast but can become saturated and cause leaks when they are compressed. By 3-6 months, you definitely need more than one insert.
If you have Alva Baby, Mama Koala or Imagine microfibre inserts, try pairing them with either bamboo or hemp which has a greater capacity to hold liquids. As hemp and bamboo are slower absorbing fabrics, you place these underneath your microfibre insert.
Make sure to take care of your nappy shells/ covers. Drying them on high heat and even excessive exposure from the hot sun can delaminate/ damage the waterproof layer of your nappies. Make sure to follow the recommendation from the nappy's manufacturer. Shells and covers dry quicker than inserts so you can just line dry them, even in the shade.
Make sure not to use fabric conditioners or softeners. If your nappy inserts are new, be sure to wash them before use. Microfibre inserts need to be only washed once. Hemp and bamboo, which have natural oils, need to be prepped. If short of time, you can soak your new hemp or bamboo inserts overnight. They will reach their full absorbency after a few washes.