This should not happen frequently, but if it does occur, not to worry! You have up to 2 hours to put it back in. As long as it hasn’t been out for more than 2 hours in the first 21 days of the cycle, you do not need to use backup contraception. Wash Annovera with mild soap and water before reinserting.
If it has been out for more than 2 hours, then use another method of birth control as back up (for example condoms) until it has been in your vagina for 7 consecutive days.