The reasons why the software cannot be downloaded are network problems, MMS content problems, and terminal problems.

1. Network problems: MMS requires network support before downloading. If the current network is unstable or the signal is poor, MMS downloading may fail.

2. MMS content problems: MMS content has problems such as incorrect format, excessive content, or sensitive information, which prevents normal downloading.

3. Terminal problem: There is a software or hardware failure in the mobile phone terminal, resulting in the inability to receive and download MMS messages normally. Try restarting your phone to see if that resolves the issue.