The Passbook(รักแลกภพ)

A modern day reckless influencer gets transported back into the past where he meets his look-alike great grandfather. To somehow get back to the present, he needs his great grandfather's help. Matters get chaotic when he gets involved in his great grandfather's love life. If he alters who his great grandmother is he would cease to exist. What valuable lessons will he learn and how will he return to the present?