Very small silver coin with cross, maybe Middle Ages. [Resolvido]

Very small (17 mm) and thin silver coin, maybe from the Middle Ages.
One side looks like a crowned shield and can read the letters and numbre ...O...I.....8....
The other side a cross and can read ...99...LID...
Have no idea.

Pictures are not sharp and cannot be zoomed in, still I think I can recognize the coat of arms from Elbing, probably during the swedish occupation

Not under Swedish occupation. The monogram is of Sigismund III Vasa (Polish-Lithuanian ruler), and Swedish occupation coins should have Swedish rulers.

I am seeing some crossed keys under that cross, indicating this coin was struck in Riga for the Duchy of Livonia. And the 99 is the date--1599.

Here is the corresponding page:
https://en.numista.com/catalogue/pieces78799.html.

Thanks Sulfur, it was a bit difficult to see with such tiny images.

Thanks everybody for helping to identify this coin.