Problem with earpods provided with iPhone XS Max

Hello.

A few days ago, the sound on the right earpod started getting muffled. The sound on the left side is louder than on the right side. A few hours later, the right side stopped working completely. The earpods weren't dropped, nothing spilled on them, they just stopped working suddenly. I tried cleaning them with a microfiber cloth. The problem wasn't solved. There is no dust/lint on the earpods. There are no exposed wires. Mono audio is not on. Yesterday, the sound returned, but it was still muffled then a few minutes later, the sound disappeared again.