You can use:
1. dimo 笛膜 ( membrane ) with ejiao
阿胶 ( gelatine glue )
2. dimo with gluestick
3. cellophane tape
to cover the membrane hole.
Above dizi uses cellophane tape
Above uses the dimo
The cellophane tape is easier to manage. You can easily paste it on or peel it off and it doesn't go out of tune during the course of the day.
The dimo can change tone during the course of the day. So if this happens, just wet the area around the dimo and stretch the dimo over the membrane hole to adjust it taut.