Are mosquitoes immune to repellent now?

My husband and I recently celebrated our 1 year marriage anniversary. He planned the entire thing. We went to Clear Lake Manitoba for camping, swimming, hiking, and a sunset boat cruise. While we were there we bought Deep Woods Off and we also bought family splash Off. We applied vigorously and then set off on our deep woods hike. We were almost immediately mauled by mosquitoes! Every part of my body is covered in mosquito bites, there is even one on my ear. The mosquitoes are not as bad in the city. They seem to be rampant in the woods. I asked my sister about this, as she has been married 3 years and they have also gone camping. She mentioned it seems like mosquitoes are resistant to repellent and like it doesn’t affect them anymore. I’m wondering if anyone else has experienced this?