LM936258728CN is a fake or incorrect number. =/

No problem. Sometimes sellers will give you a fake number at first if something isn't in stock, then follow up with a real number later, or if you ask them...

If actually is a scam, and you paid them with a credit card, you can usually succeed in a chargeback easily and get your money back. If the money was sent by Western Union, MoneyGram, or wire transfer, though, you may be out of luck. =(

Quote from m_a_x on October 8, 2015, 19:42
HI, regarding format LM123456789CN
http://track-chinapost.com/?p=686 say:

"format 4: the number starts with “L” and ends with “CN”, i.e. LK123456789CN, LN987654321CN,LM123456789CN,
This is China Post ePacket parcel. It is almost as faster as EMS and only a little bit more expensive than airmail.
However, ePacket service is only available to limited countries such as USA, Canada, Australia,UK etc."

the format is correct, however the tracking say is wrong but other tracking sites say not registered yet

Yes, but in the case of the number LM936258728CN, the checksum is wrong.

All of these 13-character tracking numbers, of the form AAdddddddddAA -- two letters, 9 digits, two letters -- are called S10 identifiers. They're a standard maintained by the UPU, the Universal Postal Union, and items that are exchanged between two countries will almost always use them.

The first two letters denote the type of mail service; the last two are the originating country. The 9 digits in the middle are an 8 digit serial number plus one check digit. The check digit algorithm is not particularly difficult, I can post it here if y'all or interested, or should be easy to Google for it.

In the case of LM936258728CN, any S10 with the first eight digits 93625872 should have a checksum of 3, but this one doesn't; it's 8. It can't be a real number.

You're welcome! Glad I can help