VISA is the brand of a credit card company. A visa is a permit to enter and leave a country, normally issued by the authorities of the country to be visited (from Latin "charta visa", a piece of paper which has been seen).
Is this comment really helpful to the conversation?
Apparently not; some people are glad to correct their mistaken beliefs about orthography, and others are not. In this forum many people are in the former category, but apparently not you. That's fine, but I couldn't know until you replied.