The American one, 2.0 NA, petrol, has thermostat rated at 82 C. That is it will keep engine at about 82-85 C while driving.
Stationery it may go up till about 95-96, while at 95 radiator fan kicks in and engine temp should drop. With AC on, it will rarely go over 90 C.
Fully open should be by 95 C, as @Red Raspberry mentioned.
Seeing 98-99 is a tad high.
But I know that other engines have different thermostats. They vary by country...
Did you monitor the temperature somehow?
I was looking for a higher temp thermostat, but the problem I found was that with rated 86 C it was opening too slowly and when it would hit 95, even when it would fully open at that time, it would not drop below 88 to turn the radiator fan off, because it would be almost fully closed. At least that would be on idle.
When driving that is not a problem.
What thermostat (model, part number) did you use?
Oh wait, you are talking about Accent and that one by default is higher, isn't it?