Upload batch contacts nothing happened

[#1]

I used the endpoint: https://api.hubapi.com/contacts/v1/contact/batch/?hapikey=KEY
to update/create 3 contacts. 2 were supposed to be created tyronewhitaker@aol.com
tylerwhitaker@aol.com and the third was supposed to be updated. Specifically this was the data sent:
[{"email":"tyronewhitaker@aol.com","properties":[{"property":"last_salesforce_campaign_id","value":"RRRRRR1"},{"property":"firstname","value":"Tyrone"},{"property":"lastname","value":"Whitaker"},{"property":"jobtitle","value":"Web"},{"property":"company","value":"Cincom"},{"property":"phone","value":"5"},{"property":"country","value":"Australia"},{"property":"product_interest_most_recent","value":"CONTROL"},{"property":"leadsource","value":"Trade Show"}]},{"email":"tylerwhitaker@aol.com","properties":[{"property":"last_salesforce_campaign_id","value":"SSSSS2"},{"property":"firstname","value":"Tyler"},{"property":"lastname","value":"Whitaker"},{"property":"jobtitle","value":"Web2"},{"property":"company","value":"Cincom"},{"property":"phone","value":"6"},{"property":"country","value":"New Zealand"},{"property":"product_interest_most_recent","value":"ECM"},{"property":"leadsource","value":"Website - Cincom"}]},{"email":"tyteach@aol.com","properties":[{"property":"last_salesforce_campaign_id","value":"TTTTTT3"},{"property":"firstname","value":"Ty"},{"property":"lastname","value":"Whitaker"},{"property":"jobtitle","value":"Web3"},{"property":"company","value":"Cincom"},{"property":"phone","value":"7"},{"property":"country","value":"Colombia"},{"property":"product_interest_most_recent","value":"Smalltalk"},{"property":"leadsource","value":"Word of Mouth"}]}]
I received a 202 "Success" However after waiting for over an hour, the contacts and/or the updates did not appear to have completed.

Any ideas?

[#2]

Now I have gone as far as using your example data: { "email": "testingapis@hubspot.com", "properties": [ { "property": "firstname", "value": "Codey" }, { "property": "lastname", "value": "Huang" }, { "property": "phone", "value": "555-122-2323" } ] } , received the 202 code and still have not seen the contact appear.

[#3]

Have now gone to simply sending ONLY an email address: { "email": "testingapis@hubspot.com"}
received a 202 success code. And that email STILL does not appear in Hubspot.,

[#4 · Accepted solution]

I resolved my issue using the Header information

Content-Type: application/json