There are many commercial or non-government websites that are deceiving people into believing that they can help them increase their chances of winning the Green Card lottery by claiming they are Green Card Lottery experts, and will contact potential victims by e-mail in order to lure them to their offers. But, that is absolutely baseless because no one can increase the chance of you winning the Green Card lottery. And of course, correctly entered entries have a better chance of getting qualified. However, no one can increase the chance of winning the lottery itself among qualified entries.
You should apply only on websites with names ending with ".gov" because they are official U.S. government websites. Other non-governmental websites with names ending with ".com", ".org", or ".net" provide immigration and visa related information and services, but the U.S. Department of State does not endorse, recommend or sponsor any information or material shown on those websites.
Please note that the only official way to apply for the U.S. green card lottery is to apply online at the Department of State website at https://www.dvlottery.state.gov/, and there is no fee to apply. If you have been selected in the green card lottery, you will receive the confirmation by postal mail, and NOT by email. Therefore, if you receive any such email, it is a scam.
It is recommended that you complete the green card lottery online application yourself, rather than through "Visa Consultants" or "Visa Agents" or other facilitators who offer to submit an application on your behalf because many of the websites offering the Diversity Visa (DV) Program extort money from their applicants by withholding their selection notifications that should have gone to the applicants directly in the first place.
The U.S. Government does not employ any outside consultants or private services to operate the DV program. Any intermediaries or others who offer assistance to prepare DV entries do so without the authority or consent of the U.S. Government. Use them entirely at your own risk.
Remember, some websites may not even provide any assistance in completing the online form or provide any service and just steal your money. Therefore, you should be very careful when sending any personal information to these websites as they might use your information for identity theft or in other fraudulent activities.