iOS 18.5 CarPlay data drop out

Using an iPhone 13 to connect via Apple CarPlay. Initially, everything works ok via (UK) O2 with either an E/3g/4g/5g connection. However after around 5 to 15 minutes the data connection drops out even in a strong 5g area. The solution is to disconnect/reconnect the iPhone connection via the CarPlay settings, which restores the data connection temporarily for another 5 to 15 minutes. Following data drop out, the iPhone indicates no data connection but after parking and car switch off. The data connection is immediately restored, ok on the iPhone.