After installing lamp in ubuntu, the XML encoding and content returned by the debugging WeChat platform are not normal. May I ask why?

The WeChat official account changed from virtual space to its own vps, using Ubuntu 14, installed lamp, and used php5.6. After debugging WeChat, I found that the content of the response to WeChat was wrong. After var_dump, I found that the normal message should be



< /URL>
Such
actually returns
'&let;xml>&let;URL>&let;/URL>
Like this, I think there is something wrong with the format, please help me, thank you.

Reply content:

The WeChat official account changed from virtual space to its own vps, using Ubuntu 14, installed lamp, and used php5.6. After debugging WeChat, I found that the content of the response to WeChat was wrong. After var_dump, I found that the normal message should be



< /URL>
Such
actually returns
'&let;xml>&let;URL>&let;/URL>
Like this, I think there is something wrong with the format, please help me, thank you.