Probably like the craigslist list jungle, Backpage has a lot of competitors flagging your ads, probably with automated software.
Geo Specific private premium virgin IPs
Fresh account created for a specific area with these geo specific IPs
Virtual Card Number for one time use
valid phone number
All fresh content; text, headline and photos
Clean browser with no cookies, no plugins
50/50 chance ad will stay up for longer then 3 hours to a week otherwise it's removed within 15 - 50 minutes, card charged with no rhyme or reason why it was pulled.
Next
Post with old headline, out of state IP address that's been abused countless times with plenty of ads taken down as a result
Virtual card number
bogus number
Ads stick 50 percent of the time, other times they go down.
Facts: Backpage has employees that look at the ads and decide whether they happen to like it or not. One guy might get lazy and let it go while another gets trigger happy with the ghosting button.
Your guess is as good as mine
Last resort?
Look into aged backpage accounts that have been active with posts on it for 30 -90 days and longer. Chances are they have implemented restrictions on brand new accounts being created and immediately running to post ads in the adult section ( clean IPs or not)
There is no simple solution to this problem other then praying these a-holes go out of business and shut down, so other ad venues step up and make things easier for a while ( until they don't anymore)
Good luck ya'll