Is 1099K the form to refile a 2018 income tax referred to the year of 2017?

Your question doesn't make sense.  Do you need to amend a 2017 or 2018 return?

No. All amended returns are done on Form 1040X. 1099K is just one indication of income you got, and the total amount reported on it is added to all other sources - 1099-MISC, Cash, etc - to arrive at your Gross income, before deductions. ALL income sources must be reported; 1099K is just one source. [added] If you have a 2017 1099-K, then it goes on a 2017 return - amended or original. 2017 forms can not go on a 2018 return.