Invalid next schedule

Hi!
Thank you for the nice plugin!

After clicking “START SHARING”, the first post is successfully sent to Twitter, but the next scheduled post somehow fail to sent and logging the message “ERROR @ 27-05-2015 07:08:16 AM – Invalid next schedule: Jan 1, 1970 @ 0:00”

## Please include this information when posting support requests ##

## BEGIN ROP CONFIGS ##

## ROP POST FORMAT

##twitter

Post Content : title
Length : 140
Post Content Custom Field :
Additional Text : 今日のオススメ記事
Additional Text At : beginning
Include Link : true
Fetch URL From Custom Field : off
URL Custom Field :
Use URL Shortner : off
URL Shortner Service : is.gd
Hashtags : nohashtag
Common Hashtags :
Maximum Hashtags Length : 0
Hashtag Custom Field :
Post with Image : off

##facebook

Post Content : title
Length : 140
Post Content Custom Field :
Additional Text :
Additional Text At : beginning
Include Link : true
Fetch URL From Custom Field : off
URL Custom Field :
Use URL Shortner : off
URL Shortner Service : is.gd
Hashtags : nohashtag
Common Hashtags :
Maximum Hashtags Length : 0
Hashtag Custom Field :
Post with Image : off

##linkedin

Post Content : title
Length : 140
Post Content Custom Field :
Additional Text :
Additional Text At : beginning
Include Link : yes
Fetch URL From Custom Field : off
URL Custom Field :
Use URL Shortner : off
URL Shortner Service : wp_short_url
Hashtags : nohashtag
Common Hashtags :
Maximum Hashtags Length : 20
Hashtag Custom Field :
Post with Image : off

##xing

Post Content : title
Length : 140
Post Content Custom Field :
Additional Text :
Additional Text At : beginning
Include Link : yes
Fetch URL From Custom Field : off
URL Custom Field :
Use URL Shortner : off
URL Shortner Service : wp_short_url
Hashtags : nohashtag
Common Hashtags :
Maximum Hashtags Length : 20
Hashtag Custom Field :
Post with Image : off

##tumblr

Post Content : title
Length : 140
Post Content Custom Field :
Additional Text :
Additional Text At : beginning
Include Link : yes
Fetch URL From Custom Field : off
URL Custom Field :
Use URL Shortner : off
URL Shortner Service : wp_short_url
Hashtags : nohashtag
Common Hashtags :
Maximum Hashtags Length : 20
Hashtag Custom Field :
Post with Image : off

## END ROP CONFIGS ##

## Begin Remote Data

Beta User: off
Remote Check: on

## End Remote Data

## Begin CRON Info

CRON Active: yes
Alternate WP Cron: no
Time now: May 27, 2015 @ 7:09
ROP Crons:

## End Cron Info

##Begin General Settings:

Minimum interval between shares : ３
Minimum age of post to be eligible for sharing : 0
Maximum age of post to be eligible for sharing : 0
Number of Posts to share : 1
Share old posts more than once : on
Post Type : post
Google Analytics Campaign Tracking : off
Exclude Specific Categories :

##End General Settings

### Begin System Info ###

Multisite: No

SITE_URL: http://example.com
HOME_URL: http://example.com
ROP Lite Version: 7.0.5
WordPress Version: 4.1.4
Permalink Structure: /archives/%post_id%
Active Theme: Example theme for example.com 0.1.0
PHP Version: 5.5.23
MySQL Version: 5.6.23-72.1-log
Web Server Info: nginx/1.6.2
WordPress Memory Limit: 40M
PHP Safe Mode: No
PHP Memory Limit: 256M
PHP Upload Max Size: 4M
PHP Post Max Size: 4M
PHP Upload Max Filesize: 4M
PHP Time Limit: 90
PHP Max Input Vars: 1000
PHP Arg Separator: &
PHP Allow URL File Open: Yes
WP_DEBUG: Disabled
WP Table Prefix: Length: 3 Status: Acceptable
Show On Front: posts
Page On Front: (#0)
Page For Posts: (#0)
Session: Disabled
Session Name: PHPSESSID
Cookie Path: /
Save Path: /var/tmp/php/session
Use Cookies: On
Use Only Cookies: On
DISPLAY ERRORS: N/A
FSOCKOPEN: Your server supports fsockopen.
cURL: Your server supports cURL.
SOAP Client: Your server does not have the SOAP Client enabled.

ACTIVE PLUGINS:

Many 😉

### End System Info ###

##Begin Log info

NOTICE @ 27-05-2015 07:08:16 AM – Post XXXXX has been successfully sent to Twitter.
ERROR @ 27-05-2015 07:08:16 AM – Invalid next schedule: Jan 1, 1970 @ 0:00
ERROR @ 27-05-2015 07:08:19 AM – Invalid next schedule: Jan 1, 1970 @ 0:00
ERROR @ 27-05-2015 07:08:21 AM – Invalid next schedule: Jan 1, 1970 @ 0:00
ERROR @ 27-05-2015 07:08:21 AM – Invalid next schedule: Jan 1, 1970 @ 0:00
ERROR @ 27-05-2015 07:08:24 AM – Invalid next schedule: Jan 1, 1970 @ 0:00
ERROR @ 27-05-2015 07:08:27 AM – Invalid next schedule: Jan 1, 1970 @ 0:00
ERROR @ 27-05-2015 07:08:30 AM – Invalid next schedule: Jan 1, 1970 @ 0:00
ERROR @ 27-05-2015 07:08:30 AM – Invalid next schedule: Jan 1, 1970 @ 0:00

#End log info

##Begin user info

TWITTER accounts – 1
FACEBOOK accounts – 0
LINKEDIN accounts – 0
XING accounts – 0
TUMBLR accounts – 0

##End user info

https://wordpress.org/plugins/tweet-old-post/