Reward negative derivative on linear regression
It's a classic outlier. You could, for example, remove him or replace him with a new value(by interpolation).
You have many ways to work around this problem.

Links for you:

https://towardsdatascience.com/ways-to-detect-and-remove-the-outliers-404d16608dba

With some code:
https://towardsdatascience.com/5-ways-to-detect-outliers-that-every-data-scientist-should-know-python-code-70a54335a623