New changes in 2022: On December 23, 2022, the IRS announced that calendar year 2022 will be treated as a transition year for the reduced reporting threshold of more than $600. For the years before 2022, third-party settlement organizations who issue Forms 1099-K are only required to report transactions where gross payments exceed $20,000 and there are more than 200 transactions.

1. What is Form 1099-K?
   
   Form 1099-K, Payment Card and Third-Party Network Transactions is an information return that reports the gross amount of reportable transactions for the calendar year to the IRS.  
   
   
2. What is Gross Amount?
   
   The “gross amount” means the total dollar amount of total reportable payment transactions for each participating payee without regard to any adjustments for credits, cash equivalents, discount amounts, fees, refunded amounts, or any other amounts. The dollar amount of each transaction is determined on the date of the transaction.
   
   
3. Who Need to File?
   
   Every payment settlement entity or other party which submits instructions to transfer funds to the account of a participating payee, in settlement of reportable payment transactions, must file an information return (Form 1099-K) with respect to each participating payee for that calendar year.
   
   You should have received a Form 1099-K by January 31 if you received a payment in the previous calendar year (1) From all payment card transactions (e.g., debit, credit, or stored value cards), and (2) In settlement of third-party payment network transactions that exceed the following declaration thresholds:
   
   • For returns for calendar years prior to Jan 1, 2022 (reach following both requirements):
      - Gross payments that exceed $20,000
      - More than 200 such transactions
   • For returns for calendar year after Jan 1, 2022 (reach following both requirements):
      - Gross payments for goods or services that exceed $600
      - Any number of transactions.
   
   
4. When is the Due Date?
   
   Form 1099-K is required to be filed with the IRS in the following manner:
   
   • Filed on paper - no later than February 28th of the year following the transaction.
   • Filed electronically - no later than the last day of March of the year following the transaction.
   
   
5. What Should Taxpayers Do if Receiving a Form 1099-K?
   
   If you receive a Form 1099-K, it generally includes the total of all reportable payment transactions from payment processors. Once you’ve gathered all of your business income, including that reported on Form 1099-K, you'll use the information for Forms 1120, Forms 1120S, or Forms1065.
   
   When a taxpayer receives a Form 1099-K, the information that should be checked first is as follows:
   • The Form 1099-K is belong to you or is a duplicate.
   • The Filer / Payee information and Taxpayer Identification Number (TIN).
   • The gross amount of payment card/third party network transactions.
   • The number of payment transactions.
   • The Merchant Category Code (MCC) is correctly describe your business.
   
   If information is incorrect, please consider the following:
   • If the Form 1099-K does not belong to you, contact the Payment Settlement Entity (PSE) listed on the Form 1099-K to try to determine the reason you received the document. The name and phone number should appear on the bottom left of the form.
   • If the form is incorrect, contact PSE for a corrected Form 1099-K.
   

Reference:
https://www.irs.gov/businesses/understanding-your-form-1099-k
https://www.irs.gov/newsroom/irs-announces-delay-for-implementation-of-600-reporting-threshold-for-third-party-payment-platforms-forms-1099-k