What Guide, and in what context? There are hundreds of Guides. If you are trying to enter a starting balance, you would only do this if you are migrating from a prior accounting system. A negative asset is the equivalent of a liability, and they do not appear by magic in the records of a business. A credit card account records a liability of the business only if the business purchase something. The credit recorded must then be balanced by a debit to some expense account.
It sounds to me like you are mixing use of a pre-existing card with business transactions for a new business. That is extremely problematic for too many reasons to list.
Your incorrect attempt to record paying off part of your credit card balance (as described by @Joe91) effectively told the program that you incurred more debt on the credit card by paying it.
You’ve heard this advice before, but it bears repeating. You simply cannot use a double-entry accounting system (the tool) without understanding what the tool is supposed to accomplish. You must educate yourself on the fundamentals of accounting first. Without meaning to be harsh, I would observe that many of the things you have reported (in other threads) trying to do are equivalent to trying to drive a nail with the handle of a hammer instead of the head. The quote I opened this response with is an example. You said, “…the guide says i have to enter the balance as negative….” Until you understand why a balance should be negative (if indeed it should be under the circumstances), you should not enter anything.