Passport

am due to travel in May 2019. My passport expires in August 2019. My current passport is in my maiden name and so are my flight tickets. If I get a new passport then my flight tickets will be invalid but I am being told I won’t be able to get a visa on arrival without 6 months left in my passport. I am planning on staying from 10th May and departing on 24th May so less than 15 days. Will I be refused entry with less than 6 months on my passport? I have applied for a visa already online and received e mail telling me I have been approved as another website told me to get my visa online in which case I would only need 1 month on my passport