Colosseo Arvostelua 

I think it’s a well known issue but you cannot purchase the in demand tickets from this website, it goes from saying no tickets available on the selected dates and when they realise them at 8:30am (Rome time) to sold out instantly (and when I say instantly in the time it takes to refresh a webpage) and then they are only available from resellers for the same money you could buy an entire holiday to Rome.

Seriously corrupt system from which some people are seriously profiting at the expense of genuine buyers.

Oggi, armata di tanto entusiasmo, ho portato i miei parenti a visitare il parco archeologico del Colosseo.
Ho offerto il biglietto, €24x3=€72 totali.
Sconsigliatissimo: un caos totale!
Volevo segnalare l'organizzazione imbarazzante del sito. Intanto c'è una confusione assurda con i giorni: la Casa di Livia è chiusa il martedì, quella di Augusto il lunedì, ma oggi in quella di Augusto non funzionavano né i proiettori laser né la voce guida. Praticamente un tour a metà.
La cosa più assurda però è l'orientamento:
• Mappe inutili
L'App dedicata si impalla continuamente e perfino gli operatori dicono che tra loro non riescono a comunicare perché non c'è campo.
Insomma, paghi un biglietto caro (e pure la mappa!) per trovarti in un labirinto senza supporto e senza servizi funzionanti. Infatti, siccome le mappe sui pannelli sono illegibili, ho anche acquistato la guida cartacea a €4,90 ma i numeri di riferimento dei siti non corrispondono a quelli che trovi sul percorso! Quindi un altro furto!
• Segnaletica e Uscite: Le uscite non sono indicate, o comunque sono segnalate pochissimo e male. Ti ritrovi a girare a vuoto senza capire dove andare.
• Personale assente: Il personale si trova solo all'ingresso dei siti che prevedono il controllo del pagamento extra, ma per il resto del percorso non c’è nessuno. Se qualcuno si dovesse sentir male non si sa letteralmente a chi rivolgersi!
• Pannelli illeggibili: I cartelli sono lontanissimi (2 metri dalle transenne) e sbiaditi dal sole, non si riesce a leggere nulla.
Come se non bastasse, la gestione delle lingue è un disastro (tocca aspettare anche 40 minuti per sentire la propria) e neanche il personale addetto sa dirti quanto devi attendere (se sapessi di dover aspettare 40 minuti, ottimizzerei il mio tempo per vedere altro per poi ritornare).
La rete cellulare è a singhiozzo. Un vero peccato per un posto così bello gestito così male!

Its a sham!

The slot appears, fastest click in the world on the date and time available, even faster with number of tickets needed- all this done in 2 seconds max, and tickets sold out, within 5-6 seconds of slot being available.

And no customer service will reply here, because I guess its just an agreed deal with the third-parties to share the fare.

I made a simple mistake while booking a ticket – I selected the wrong date. When I contacted customer service to fix it, I was met with a cold, copy-paste reply citing inflexible regulations and absolutely no willingness to help.
No date change, no refund, no understanding — even though the ticket wasn’t used and the visit hadn't happened yet. They told me it’s entirely the buyer’s responsibility, regardless of how small or genuine the error is. Apparently, even changing the time or date by a single day is “impossible.”
I have never experienced such rigid and unhelpful service in any other museum or cultural site across Europe. This kind of attitude is completely unacceptable for a world-class attraction like the Colosseum. They treat visitors like numbers, not people.
Avoid booking directly through colosseo.it unless you're 100% sure you won’t make even the smallest mistake — because they certainly won’t help you fix it.

Only official web of Colosseo with ticket sales... We book through 3-rd party with many problems and 60% more expensive. You can book on this page also Free of charge having your ROMA CARD incl. Roma public transport.

They clearly purposely allow bots or special access for those to gain the more exclusive tickets.
These people then resell for 5 times the price.

Nothing is done to stop them, tourists are just seen as money money money

I am writing to share an extremely disappointing experience we had with your service. We purchased family tickets for five people, but there was a mistake in my mother-in-law’s surname on her ticket. I understand that changes are only allowed up to seven days before the appointment date, which is fine. However, when I tried to purchase a new ticket with the correct information, I discovered that your system doesn’t allow a second ticket purchase with the same email address on the same day.

When I contacted customer support, they advised me to buy a new ticket on-site. Unfortunately, upon arrival, there were no tickets available for the same time slot. This left us in a difficult situation. To make matters worse, the staff yelled at my wife because her mother had a ticket for a different time slot, even though she already held one with a minor error in the surname.

Been trying to get tickets for days now! Every timed slot I try it says insufficient tickets! Managed to get 2 tickets into my basket but when I came to pay they had disappeared! Rubbish website and still waiting almost a week later for a reply from them!