LAS VEGAS (KLAS) — Properties owned by MGM Resorts International appear to be returning to normal after it says a cybersecurity issue has impeded its services for the better part of four days.

The issue, which seems to have begun Sunday evening, brought a large number of the resorts’ digital services and amenities down including the use of digital key cards, reservation systems, casino gaming systems, and phones among other services.

On Thursday the MGM Resorts web presence was back online with a few modifications. For example, room reservations are offline and limited to phone bookings. However, visitors can book shows, make restaurant reservations, and reserve pool cabanas online.

The weekend brings an influx of visitors to Las Vegas and in turn, MGM resorts. On Thursday, those guests were starting to arrive.

“15 of my closest friends are coming,” said Jennifer Musillami, a visitor who arrived at the Las Vegas airport Thursday. “I’m not changing plans.”

Musillami said she would evaluate her resort, and if she deemed the situation too chaotic, she would move along to another option. Shawn Skeldon, who has a room reserved at Mandalay Bay Resort and Casino, said he will also evaluate the situation. However, instead of booking another room if the situation there seems disorganized, he might just head home.

“We thought, ‘Well maybe just wait it out and see what happens.'” Skeldon said. “Who knows, we may be flying back home tonight.”

The chaos has led to extended wait times, according to Sandy Slade, who is staying at Luxor Hotel & Casino.

“It took us probably two hours to check in yesterday,” said Slade, adding that the wait times extended to the resort’s casinos as well.

“If you play any of the machines, you have to wait an hour to get an attendant,” Slade said.

Slade said she was planning to use the MGM Rewards loyalty program, but due to the system outage, that will not be possible.

Non-functional gaming machines, long check-in lines, and issues accessing rooms have plagued the MGM properties since the cybersecurity issue struck on Sunday, guests say. Since then, visitors say they have stuck to cash when paying at locations inside the resorts.

“Using cash only — no swiping of any kind of cards,” one visitor said.

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