Creating Deal error: property cannot be missing or null

[treefix]

Every time I try to post a new deal I get this error "property cannot be missing or null". I do not understand why if I'm using all the required fields.
Below is my JSON data I'm sending to the hubspot api:

{"associations":{"associatedVids":[134051]},"properties":[{"name":"dealname","value":"KS Job #391"},{"name":"dealstage","value":"0582317a-70a9-4732-9bb7-2e1031f0fe6b"},{"name":"pipeline","value":"default"},{"name":"closedate","value":1531976400},{"name":"amount","value":"457.14"},{"name":"dealtype","value":"newbusiness"}]}

[treefix · Accepted solution]

I figured it out. It was the "closedate" that was causing the issue. It is supposed to be in milliseconds, not seconds.