I have been having an annoying IGNITE bug that has cost me so much in fights!!!

countless battles ignited people then i die or something then out of no where i get ignite back.....

Example: Vs a YI i ignite and almost kill before i die then he runs off still ignited which vanishes mysteriously then by the time i respawn i have ignite back off CD...

then 1st game battle we jump Brand nearly killing him and i ignite he runs off burning but i die <he needed what looked like one more ignite hit to kill, in which ignite should of killed> but instead he lives and after 1st death respawn i have ignite off of CD for no reason i used it ......