Whenever you successfully deliver a contract the contracts_fulfilled is raised by 1, and contracts_unknown decreased by 1.
Whenever you blow a contract the contracts_expired is raised by 1, and contracts_unknown decreased by 1.
The total number is always 7 (that's how far back your total reputation reaches, only the last seven contracts).
Cargo contracts get more interesting and more rewarding if contracts_fulfilled is at least 6. Therefore it is worthwhile to (successfully) do a couple of contracts in a row. The same is no so true for passenger contracts. I would seriously advise you to sell any passenger berth and use the space to haul computers/furs instead. It's much more rewarding than the passenger fees you could get in the same time.
In a second process your reputation (the memories of how successful you did past contracts) also fades with time. Technically that means that both contracts_fulfilled and contracts_expired may get randomly decreased by 1 every now and then, and contracts_unknown increases accordingly, so that the total number still is 7.
And this is what happened to you (as to every commander). You did some contracts in the past, but nobody remembers anymore, therefore your reputation is non-existent again.
In order to build a lasting reputation, you have to continuously accept and fulfil contract runs.
The system is the same for passenger and cargo contracts.
Hi as a rookie, when do you even start getting offered cargo contracts? I missed the chance of taking the only one which came up (my misytake)and have never found any available since. my basic status at this point is Cobra III with 35 tons, competent rating galaxy 1. Is my ship too small or have I not got enough hours to get offers? Grateful for any tips on getting cargo contracts offered e.g. is it only certain types of planet/
When you go to the marketplace (F8) then press F8 again. There you'll find cargo and passenger contracts, although what you can actually take depends on your hold size and whether you have any passenger berths available.