public static function isPaidAccount()
 {
     if (self::$isPaidAccount !== null) {
         return self::$isPaidAccount;
     }
     if (\COption::GetOptionString('voximplant', 'account_payed', 'N') === 'Y') {
         return self::$isPaidAccount = true;
     }
     return self::$isPaidAccount = self::isPaidLicense();
 }
 public static function isPaidAccount()
 {
     if (self::$isPaidAccount !== null) {
         return self::$isPaidAccount;
     }
     self::$isPaidAccount = self::hasPurchasedLicense() || self::hasPurchasedUsers() || self::hasPurchasedDiskSpace();
     if (!self::$isPaidAccount) {
         //Phone number check: voximplant::account_payed
         //SIP connector check: bitrix24::~PARAM_PHONE_SIP
         self::$isPaidAccount = \COption::GetOptionString('voximplant', 'account_payed', 'N') === 'Y' || \COption::GetOptionString('bitrix24', '~PARAM_PHONE_SIP', 'N') === 'Y';
     }
     return self::$isPaidAccount;
 }