Ich frage mich echt, wie man diesen Cooldown so verkacken kann.

const MAX_QUOTA = 6
const COOLDOWN_PERIOD_MS = 30000
let quota = 0
let interval = null

function regrow() {
  if (quota >= MAX_QUOTA) {
    clearInterval(interval)
    interval = null
    return
  }
  quota++
}

function onClick() {
  if (quota <= 0) { return }

  fetch(/**/)
    .then((res) => {
      if (!res.ok) { return Promise.reject(res) }
      quota--
      if (!interval) {
        regrow()
      }
    })
}

interval = setInterval(regrow, COOLDOWN_PERIOD_MS)