Internet drops out post port

I think I need to check my SIM/data provisioning and PDP/data-session configuration, and whether there is a network fault affecting my serving cell? My Moto G55 registers as 4G/4G+ and reports ‘Connected’ and ‘In service’, but mobile data intermittently stops completely. 5G preferred also fails to establish a connection. Network resets, APN checks and airplane mode have not resolved it.” this is after a port from Giffgaff. Just awful service