How to upgrade core through ftp if commerce has been installed through composer

Hello

I have this problem since I start to using D8, but don’t know how to get over it.

I firstly installed my D8 through ftp upload , and then I install commerce2 through composer.

Now I don’t know how can I upgrade my core, because when I upload the new version again , it will cause problem on the vendor folder that commerce is using.

Does anyone knows how to solve this problem, because I need to upgrade the drupal core  ? ( drupal core by ftp upload, commerce by composer)

Thank you!

Drupal version: 


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