Miranda Lambert fans in Salt Lake City, Utah, and Denver, Colo., will have to wait a little bit longer to see the singer on her Wildcard Tour. The country star has postponed her weekend shows in the cities.

"I've been doing everything in my power to be 100 percent, but my voice is just not there. Not even close," Lambert shared on social media on Friday (Jan. 31) when announced the Salt Lake City tour stop's postponement. "I am so sorry to let everyone down. Since I'm not well, we thought it would be better to come back and give y'all the best show we can."

Lambert promised that she was "medicating and resting and I'm praying I will be better to play ... tomorrow," but on Saturday (Feb. 1), she officially postponed her Denver show. "I spent the last 24 hours on the bus trying to get as well as I could. No talking. All the tea in the world. Sleep. Meds. I'm feeling a lot better but unfortunately my voice is just not back yet and there is nothing else I can do but wait," she writes.

"It's the worst feeling in the world to not be able to show up and put on a show for y'all. Especially since our bands and crews traveled so many miles to get here and make it happen," Lambert adds. "I can't apologize enough for the inconvenience. I love playing Denver and promise to bring the best show we can when we come back."

Lucky for fans with tickets to Lambert's Salt Lake City and Denver shows, she's already rescheduled them: Lambert and openers Cody Johnson and Lanco will be back in town on Feb. 25 and March 2, respectively. All tickets for the original show will be honored at the rescheduled dates.

"Thanks for understanding and please know that my heart is broken over this," Lambert writes.

Lambert's Wildcard Tour began on Jan. 16 in Tupelo, Miss., and will run through early May. The Randy Rogers Band and Parker McCollum will open select shows in place of Johnson and Lanco.

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