A cellular communication device is configured to use Non-Standalone Architecture (NSA) dual connectivity for communicating with a cellular communication network, using simultaneous 4th-Generation (4G) Long-Term Evolution (LTE) and 5th-Generation (5G) New Radio (NR) radio access technologies. When implementing NSA dual connectivity, the device may receive separate transmit power control commands for LTE uplink transmissions and NR uplink transmissions, respectively. In order to keep total transmitted power of the device below a regulatory maximum transmit power, LTE transmit power is limited to a value that is less than regulatory maximum transmit power, thereby reserving at least a reserved transmit power for NR transmissions. This allows NR acknowledgements to be sent from the device to avoid NR downlink failure.