The free OpenSignal application, available for Apple iOS and Android allows you to locate the nearest cellular repeater or locate the one to which we are already connected. The repeater will be displayed on the map and by clicking on it it will be possible to identify the operator to which it belongs and the signal frequencies distributed (2G, 3G, 4G). At this point you can decide whether to move, approaching the signal, or if you decide to use the type of network (read the following paragraph) more powerful at that point.
Set up a less demanding cellular network via Network Configuration and Change Management. The data connections of a few years ago were limited, being designed to allow simple calls or the sending of text messages. The GSM or 2G network is less demanding than the subsequent ones (3G, LTE) in terms of transmission and reception and could be ideal for environments with poor telephone coverage.