Buttons falling off. Is this normal?

No it is not normal. Buttons do occasionally fall off but it is a  rare occurance. Visit your dentist and make sure the buttons are replaced.

It’s not normal for the buttons to fall of, but it can
certainly happen in the beginning, while you are learning how to use them
properly. It’s also possible that the tooth could have gotten slightly wet
while there were trying to place them
which will contaminate the surface. Your dentist should be able to place them
back for you in no time.

If an Invisalign button is bonded onto your own natural tooth properly, it should rarely fall off. Ask your dentist why he thinks it is happening. If the tooth can be isolated properly and fresh bonding agents are used properly, they should rarely fall off.

HelloThe failure of successful bonding of buttons as well as regular braces can have multiple factors. Among them are:1.Improper bonding technique.2. Saliva/Blood contamination with the bonding agent.3. Excessive force applied to the attachment.4. Traumatic contact with opposite teeth.5. Patient lack of care by eating hard foods or 'playing" with their appliances.Don't worry , loose or broken buttons happens to the best of us, your Dr. will take good care of you and fix everything as needed.Smile!