@lafsav there are several levels around 4600 and up where they don’t allow boosters because of the introduction of the crystal candies. They will reappear once you get through these levels.
Hello @lafsav I want to wish you warm Welcome to our Divine Community!
As @Kazza-3 mentioned when new features/blockers are introduced into levels there are generally no options to add boosters to the level prior to starting. In this case it's due to the fact that Crystal Candies are being introduced 🤔
I hope this clears up any confusion you may have, and hope you have a crushtastic day!