Annoyed with work!

Work doesn't want to let me do a proper handover! I been trying to do a handover of work to my colleagues but nobody wants to accept it readily. My bosses are really useful, I have to remind them that I will be away soon every single week, yet they keep asking me to do more stuff. It's time I do lesser and starting teaching others the ropes. I been advocating this but it's falling on deaf ears. I am handling my handover myself when my reporting officer should at least check in with me to see how it's going.