We look "le stesse persone", "lo stesso errore", "nella stessa condizione", "gli stessi colleghi".
"Stessa" is feminine singular;
"Stesso" is masculine singular;
"Stesse" is feminine plural;
"Stessi" is masculine plural.
The demonstrative adjective creates a connection: in this case we have a connection of identity.
We can create new sentences.
Noi abbiamo le stesse idee. Loredana e Carla vivono nello stesso condominio. Le figlie di Marco hanno gli stessi occhi. Il medico prescrive la stessa medicina.
We have to remember a thing: we can use "stesso, stessa, stessi, stesse", but we can change it with "medesimo, medesima, medesimi, medesime". They have the same meaning.
Noi abbiamo le medesime idee. Loredana e Carla vivono nel medesimo condominio. Le figlie di Marco hanno i medesimi occhi. Il medico prescrive la medesima medicina.
Again a thing. Please, look this word: "colleghi" (colleagues). It's a masculine plural word: we say "i colleghi". At feminine plural it is "colleghe", then "le colleghe". At singular it's the same for feminine and masculine word: "collega". Therefore we can understand the gender, if we look the article: "il collega" (masculine), "la collega" (feminine), "un collega" (masculine), "una collega" (feminine). Remember: you must use "i colleghi", when you tell about some men or some men and women together.
We translate: The same people who advised me to speak to Ricci, now tell me that I got wrong. They repeat me not to do anything stupid and not to make the same mistake. I find myself in the same situation a few weeks ago, but now the same colleagues who urged me to react speak with me as little as possible.