Different types of affirmations come from different chakras depending on how they are worded. There are none for “I will” or “I have” because one puts itself in the future and the other is entirely materialistic and property ownership is not a concept in the land of spirits and ghosts. The seven affirmations for each chakra are
I am - Root I feel - Sacral I do - Solar Plexus I love - Heart I speak - Throat I see - Third Eye I know - Crown
If you are just saying “I am” then you are directing energy from your root chakra which is good, but then you are only using the root chakra. You should think about how you can phrase your desire in all the possible different ways from above, so that you can bring something into your reality from all seven chakras. It can be creative as well, such as I know I always get what I desire, or I speak thanks for the positive experiences that come into my reality. Using all seven and in present tense is the best way to direct your energy into manifestations.