OneHotEncoder报错：无法将字符串转为浮点型，求解决方法

I'm currently learning Multiple Linear Regression and working through practice exercises. When I try to use OneHotEncoder to convert the payment_type column into categorical variables, I keep hitting this error:

OneHotEncoder Error: cannot convert string to float

I've tried several online troubleshooting solutions, but the error persists. What's really confusing me is that the error mentions failing to convert 'VTS'—not the payment_type column I'm actually trying to process. Up to this point, my code only includes basic data loading steps, no other transformations have been applied.

I've attached a screenshot of my current code and the error message for reference:
Code and error screenshot

Could anyone help me figure out why this error is occurring and how to resolve it?

内容的提问来源于stack exchange，提问作者ra1993