Beaumont Health System in Michigan is cancelling nearly 2,000 COVID-19 second-dose vaccine appointments over an unexpected shortage.

The health system said in a statement on Monday that it learned of an “unexpected and significant reduction in Pfizer COVID-19 vaccine allocation from the state of Michigan,” forcing it to cancel 1,884 second-dose appointments that had been scheduled for Thursday. 

Beaumont said in its statement that it’s prepared to administer 50,000 doses a week, but instead will only be able to administer 2,200, which is all the state supplied in its recent allocation.

The health system said it has administered more than 100,000 doses since the vaccine became available two months go.

“We are so disappointed that we had to cancel these appointments. Our teams worked around the clock and throughout the weekend with the state to try and secure the second dose vaccine we requested,” Beaumont Health Chief Operating Officer Carolyn Wilson said in a statement. “We remain committed to vaccinating patients as quickly as possible as soon as we receive our allocated doses of vaccine.”

Lynn Sutfin, a spokesperson for the Michigan Department of Health and Human Services, said in a statement to The Hill that “the state has been working with Beaumont Health for the past week to reconcile their second dose shortages. It is unfortunate that they chose to cancel second doses appointments while we were continuing to work with them on this issue.”

Pfizer’s vaccine is meant to be taken in two doses three weeks apart, while Moderna’s is meant to be given in two doses four weeks apart. However, the Centers for Disease Control and Prevention (CDC) says that the second dose of both vaccines can be administered up to six weeks after the first.