Trending @Infosys; Stuck in two projects bcz of onsite opportunity

I have been working on a US based project for the last 3.5 years, and got H1B initiated for the same project in 2024 but due to the regime change in the US the H1B got on halt on the organisation level. So to compensate that my DM got me into a new project for Canada onsite opportunity, but the problem is that I am still aligned to the previous US project in which there is no near future onsite or growth opportunity for me. Now I am working on two projects simultaneously for the past 3 weeks and it's starting to get onto my nerves due to the work. Adding onto that there is a pressure for getting the release from the old project, first I was assured that the managers will align things but now they are pushing me to get the release by myself. So now the situation is my old manager doesn't know I am working on two projects and there is a dependency on me so they will not be releasing me soon. But bcz of the head-count battle of the management they are not helping me either, I don't want to lose the Canada opportunity and i really want to align things in a better way. Please suggest some ways to get out of this situation without having any repercussions with my old and new manager.