A method for handling a radio-frequency connection between a control unit and a mobile device of an access control system, wherein the control unit controls access to a physical area, to a content of a logical area, to a protected device or to a protected resource in response to a generated event in the access control system and wherein the control unit 110 is limited to a maximum number of multiple simultaneous radio-frequency connections to mobile devices, the method comprising: establishing, by the control unit and the mobile device, the radio-frequency connection between the mobile device and the control unit in response to the mobile device being able to communicate with the control unit; wherein the method is characterized by: obtaining, by the control unit, an indication of a first event generated in the access control system by the control unit in response to a first request to access the physical area, to the content of the logical area, to the protected device or to the protected resource, wherein the indication of the first event is obtained when the mobile device is connected; attempting to determine by the control unit which connected mobile device out of one or more connected mobile devices that is associated with the first event by sending requests to the one or more connected mobile devices requesting them to respond with indications of whether or not they are associated with the first event; after a release of the connection by the control unit, obtaining, by the control unit, within a pre-determined time duration from the release of the connection, during which pre-determined time duration the mobile device is prohibited from re-connecting to the control unit unless a second event has been generated in the access control system during the predetermined time duration in response to a second request to access the physical area, to the content of the logical area, to the protected device or to the protected resource, an indication of whether or not the second event has been generated by the control unit; and determining, by the control unit, based on the indication of whether or not the second event has been generated, whether or not to allow the mobile device to re-connect to the control unit within the pre-determined time duration from the release of the connection, such that it is possible to determine whether or not a re-connected mobile device is associated with the second event. obtaining, by the control unit, an indication of a first event generated in the access control system by the control unit in response to a first request to access the physical area, to the content of the logical area, to the protected device or to the protected resource, wherein the indication of the first event is obtained when the mobile device is connected; attempting to determine by the control unit which connected mobile device out of one or more connected mobile devices that is associated with the first event by sending requests to the one or more connected mobile devices requesting them to respond with indications of whether or not they are associated with the first event; after a release of the connection by the control unit, obtaining, by the control unit, within a pre-determined time duration from the release of the connection, during which pre-determined time duration the mobile device is prohibited from re-connecting to the control unit unless a second event has been generated in the access control system during the predetermined time duration in response to a second request to access the physical area, to the content of the logical area, to the protected device or to the protected resource, an indication of whether or not the second event has been generated by the control unit; and determining, by the control unit, based on the indication of whether or not the second event has been generated, whether or not to allow the mobile device to re-connect to the control unit within the pre-determined time duration from the release of the connection, such that it is possible to determine whether or not a re-connected mobile device is associated with the second event.