微信号是不可以改第二次的。
修改微信号的具体操作步骤如下：
1、首先在微信“我”的页面中点击最上方的个人信息栏。
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2、然后就会跳转到“个人信息”的页面，在此页面点击“微信号”选项。
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3、然后在“设置微信号”的页面中输入新的微信号，确认无误后，点击右上方的“完成”。
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4、接着此时会弹出一个再次确认的页面，在此页面中继续点击“确定”就可以了。切记，微信号只能进行修改一次。
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