Redmi 1s crashes and restarts, and the message disappears. How to get it back? No backup

Under normal circumstances, whether it is stored in a mobile phone or a card, it can't be retrieved if it disappears again. This is a systematic problem, just like being deleted, and it is impossible to get it back. Because information is not like software files, some contents will be cached in the phone memory or memory card, so important information must be copied and stored in the cloud (some contents are unsafe and easy to leak in the cloud), or the copied contents will be stored in the memory card. If it crashes again, it may be that there is a BUG in your mobile phone. It is recommended to refresh it (under the guidance of professionals, or the matters that novices should pay special attention to when learning materials online), or upgrade the system, and if necessary, you can go to the mobile phone shop for consultation!