Unfortunately 99% of sellers have a different view of what constitutes Full Service History than me, or rather I should say that I have a different view of Full Service History than 99% of sellers.
To me it means all services operations have been completed on-time and in-line with the manufacturer's service schedule, including additional time or mileage based items like spark plugs or transmission fluid.
I genuinely can’t remember the last time I enquired about a car advertised with FSH or FMBSH which actually had it when I was shown the service history, even cars as young as say three years old have gaps.
Once a car is older than that - whether it’s high mileage or low mileage, expensive or inexpensive when new - the majority of cars appear to be serviced every 2, 3 or 4 years and without any real pattern.
As a result I ask sellers for a breakdown of services with date, mileage, and servicing dealer/garage - or photos showing the same - and I simply don’t travel to view it unless it’s close to what I expect.
Having asked - main dealers, traders and private individuals - many explain “full” as meaning that the history of everything “done” to the car is present, which often almost certainly isn’t the case either.
I’ve lookee at countless cars from the mid noughties recently - ranging from 5,000 to 125,000 miles and with new prices between £15,000 and a lot more - and none were even close to following the schedule.
If the OPs car is just a few years old, it’s ununusl to have no service history, however once the OP has owned it for a few years more then it will be pretty much the same as the majority of cars for sale.