There could be several reasons why your foundation appears orange on your skin:
Incorrect shade: If you have chosen a shade that is too dark or too warm for your skin tone, it can make your foundation look orange.
Oxidation: Some foundations contain ingredients that can change color when exposed to air and light, causing them to look darker and more orange over time.
Natural skin undertones: Our skin has natural undertones, such as pink, yellow, or olive, which can affect the appearance of makeup. If you have a warm skin tone, it's best to choose a foundation with yellow or olive undertones to match your skin.
Sun tan: If you have recently tanned your skin, it can affect the way your foundation looks, making it appear orange.
To avoid this problem, it's important to choose the right shade of foundation for your skin tone, and to test the shade on your jawline or neck to ensure a good match. If you're still unsure, consider consulting with a makeup artist or esthetician for assistance.