The Russian government initially struggled to get coronavirus vaccines into people's arms, facing a wary public.
But now some regions have a new problem: People are finally lining up to get vaccinated - and there are shortages.
One resident in the town of Vladimir said people were lining up at 4 a.m. for centres opening at 10 a.m.
Eugenia is a health inspector in the town:
"The first month of vaccination, we had about 20-25 people during working hours. Right now, it can be 70-80 or 50, it depends on how many vaccines we have. So yesterday we did 80 vaccinations, today we have only a certain amount of vaccines; it's just 50 because we only have 50 doses, that's all."
Reuters went to the appointment desks of four different clinics around there last week. They all said no shots were available.
The earliest appointments were next month, and all said they could not give an exact date.
Sergey Sobyanin is Moscow’s Mayor:
"During the last six months, 1.7 million people in Moscow got the first vaccine. Now, during the last month - only a month- there’s been more than two million!"
The country’s vaccine drive was initially slow, in part due to skepticism.
But now, Russia is battling a record third wave of COVID-19 infections.
And vaccination is compulsory in some Russian regions for people working in jobs involving close contact with the public like waiters and taxi drivers.
The switch poses a challenge for Russia, which has also signed contracts to supply its Sputnik V vaccine to countries around the world.
Russia is producing 30 million sets of doses per month, according to the industry ministry.
Russian Prime Minister Mikhail Mishustin ordered the government on Monday to check what vaccines were available for Russians.
The industry ministry said it was working with the health ministry to close the demand gap in places where it had jumped. The health ministry did not respond to a request for comment.