Problem with deadlock on AWS RDS MySQL

Hello,
We have an issue regarding AWS RDS MySQL.
We have migrated from an AWS EC2 MySQL to RDS MySQL for improving performance, stability and reliability but we are facing a big issue.
After we migrated the databases and started a few php crons that are inserting in MySQL various data(statistics for our application) using INSERT .. ON DUPLICATE KEYS UPDATE we are constantly receiving the following error when the cron is being executed: "Deadlock found when trying to get lock; try restarting transaction
Query: INSERT INTO.."
We are using InnoDB engine.
We have used mysql 5.6.24-log on the EC2 Instance and now on RDS we are using 5.7.21-log.
Parameter group: default.mysql5.7.

Thank you!

Edited by: numanx on Jun 13, 2018 5:29 AM