The phrase "to contact the users" means to reach out or communicate with the individuals who use or interact with a particular product, service, or platform. Full definition
If you wish to contact any user on Date Over 60, you must create a 100 % Free Account to ensure you are who you say you are. (dateover60.com)
It is also why fake dating sites are doing so well: They have bots that contact users in order to jump start communication. (blogs.elenasmodels.com)
We may also contact any user of this online system for audit and verification purposes in order to comply with laws and regulations governing the credit reporting industry. (imc-us3.csid.co)