If you upgraded, then please ask the question somewhere else.
If you’re having trouble activating the Elementor license, please also ask Elementor about this. It’s their code that’s not working. and although it may not be their fault, they may still have an idea as to why this happens.
And if you upgraded your account, then please note that the premium hosting is not provided by InfinityFree but by iFastNet (so you can/should ask them for help), and that your account will need to be migrated to premium hosting to get the benefits of the premium account.