Leveling character skills
 

Not sure what I'm doing wrong, but every time I try to add new skills (as in, during gameplay a checked skill can result in a skill increase), it results in an "invalid" result as if I'd just created the character anew.

I know how to level up (by adding experience in the Journal tab) for other systems, but how do I resolve this for Call of Cthulu (7e)?

What does the "invalid" result look like? Is there an error message being reported? If so, you can right-click error messages in HL and copy them. Then I'd paste it here, because right now, I don't understand what you're reporting.