Apparatuses, methods, and systems are disclosed for modifying a data connection. One apparatus (500) includes a processor (505), a first interface supporting (705) a first data connection with a 5G core network over a first access and a second interface that communicates with a UE over a second access. The processor (505) receives (710) a request to establish a second data connection with the UE and determines (715) whether the second data connection can be mapped into one of a plurality of QoS flows established over the first data connection. The processor (505) sends (720) a request to establish a new QoS flow over the first data connection upon determining that the second data connection cannot be mapped into an existing QoS flow of the first data connection and relays (725) traffic between the second data connection and the new QoS flow over the first data connection.