For your reference, please check the following details:
1. Check if there is too much debris in the dust compartment. If so, clean the dust compartment promptly;
2. Check if the the extension tube or the vacuum cleaner hole are blocked. If so, remove the foreign objects promptly;
3. Check if the filter assembly is clogged with too much dust. If so, clean it promptly;
4. If the filter has been washed, ensure it is thoroughly dried before using it again;
5. If the above methods don't help, please apply for the after-sales service promptly.