As we do see the character of Mónica Gaztambide in her underwear for most of the first season, it is quite obvious that her underpants change from white to black half-way through the show.
In one of the first episodes Tokio is supposedly 12 years older than Río. Later on, Berlín and others remind Río that his girlfriend is 15 years older than him.
When the Professor finds Tokyo, she is on the lam and wanted all over the country, but later she travels to the mint and other places without any concern that she'll be recognized.
When the Police scope out the entry points using optics, Suarez identifies the machine gun as a "Browning", when clearly it's an MG42. Later on in the series, the gun sounds like a 30 or 50 caliber weapon firing (a slow thud-thud-thud) when in reality the MG42 fired at 1200 rounds a minute, nearly double the amount of the Browning's 650 - 850 rounds a minute.
In season 1 when Arturito and Denver are in the vault fighting, Arturo mentions that his "son" that Monica is having wouldn't like Denver knocking on his door. However, it would be too early to find out the sex of the baby. Even if they did know it was a boy, the season 3 when Denver is surprised and excited to have a boy wouldn't make sense.
Also, in season 3, Arturito is talking to his fans about his poor son. If they are in hiding, then Arturito wouldn't know the sex of the child.
Further Details: The above is not a revealing error but actually a translation error. "Mi hijo" does mean "my son" in Spanish but it depends upon context. If the gender is unknown that "mi hijo" would therefore be correctly understood as "my child" and this should have been reflected in the translation. The original Spanish dialogue however, is in fact correct.
Also, in season 3, Arturito is talking to his fans about his poor son. If they are in hiding, then Arturito wouldn't know the sex of the child.
Further Details: The above is not a revealing error but actually a translation error. "Mi hijo" does mean "my son" in Spanish but it depends upon context. If the gender is unknown that "mi hijo" would therefore be correctly understood as "my child" and this should have been reflected in the translation. The original Spanish dialogue however, is in fact correct.
The question arises, how can one small truck carry a load of 45 tons considering that they were transporting 90 tons of gold with two smaller trucks.
When the Professor and Helsinki leave the warehouse in the beer truck, the police can already be seen on the street heading towards them. Because the police know the address, they would have seen the truck leave it and thus should have stopped it.
No matter how fluent in a language, you always pronounce your own name as in your native tongue. The actor playing Alison Parker clearly has no idea how her character's name would be pronounced in English. She also pronounces the English town of Norwich with the w sounded, which no English speaker would do.