The massive giveaway at EPIC, where you can key a free license to GTA-V, has had an effect on the Rocketstar servers, downtime and connection problems were caused by the large number of new players.
Rockstar Games confirmed on Sunday that there were connection issues with Rockstar Games Services, including the Rockstar Games Launcher and GTA V for the PC.
GTA V servers for PC had downtime due to large influx of players