恕我直言，老外英语讲得好，但不懂语法、讲错句子者大有人在。

语法规定：动名词和现在分词的否定式，not 在前，doing 在后。即：

not doing （正） not being （正）

doing not（误） being not （误）

如果老外坚持违背语法规则的表达，即便存在也是不规范的。

有权威词典为证：

What scares me most is that I'm going to end up not being married. 

最让我担心的是我会一辈子嫁不出去。

来自柯林斯例句

Not being a mother, I found the chit-chat exceedingly dull.  

我没当母亲，所以觉得那样的闲谈无聊透顶。

来自柯林斯例句

Not being able to speak the language made me feel strange.  

由于不会说那种语言,我感到很不自在。

来自《现代英汉综合大词典》

Not being able to hear doesn't seem as bad as not being able to see

看不见比听不到更让人难以忍受。

《柯林斯高阶英汉双解学习词典》

He sounded peeved about not being told.  

没人通知他，为此他气哼哼的。

来自《权威词典》

She was chiding her son for not being more dutiful to her.  

她在责骂她儿子对她不够孝尽。

来自《简明英汉词典》

He felt aggrieved at not being chosen for the team.  

他因没被选到队里感到愤愤不平。

来自《简明英汉词典》

He said he much regretted not being able to help.  

他说,他帮不上忙,深感遗憾。

来自《简明英汉词典》