Tumblr not posting

Hello!

The plugin stopped posting on Tumblr, even if the test post works. I get this error in logs:
-=ERROR=- Array ( [pgID] => [isPosted] => 0 [pDate] => 2017-02-09 02:38:04 [Error] => 400 – Bad Request | stdClass Object ( [meta] => stdClass Object ( [status] => 400 [msg] => Bad Request ) [response] => stdClass Object ( [errors] => Array ( [0] => Error uploading photo. ) ) ) )

I read the FAQs and followed the advice here – https://wordpress.org/support/topic/twitter-posts-not-posting-images/
After I created that page and accessed it, I am receiving no error, but:
Array
(
[headers] => Array
(
[server] => nginx/1.10.1
[date] => Fri, 10 Feb 2017 21:02:42 GMT
[content-type] => image/jpeg
[content-length] => 144225
[last-modified] => Mon, 29 Dec 2014 09:24:55 GMT
[connection] => close
[etag] => “54a11de7-23361”
[expires] => Sun, 12 Mar 2017 21:02:42 GMT
[cache-control] => max-age=2592000
[accept-ranges] => bytes
)

[body] => ����JFIF��C

You can check the file here: http://yaoimangaonline.com/imgtest.php

What could be done to fix it?