payment_instrument_id is not a valid integer | Importing contribution
If you guys found similar issue with me. Please check whether you've already made some changes to Payment Method option value which is by default you could access it by http://yoursiteurl.com/civicrm/admin/options/payment_instrument?reset=1

Revert the changes you've made to default value, and try to re-upload/re-import the contribution. It solved my problem.