Somebody looked up your two signs, read that you're incompatible, and now it's sitting in the back of your mind even though things are going well.
Let's take that idea apart properly, because it's built on a shaky foundation.
The compatibility charts you've seen compare one placement out of dozens
Sun sign compatibility compares two data points. A full chart contains the Moon, rising sign, Venus, Mars, every other placement, twelve houses and the aspects between them all.
Judging two people by sun signs alone is like deciding whether two people will get along based only on their jobs. It's real information. It's a fraction of the picture.
Difference is not the same as incompatibility
This is the part the charts get most wrong. Two people who process the world differently often build something more durable than two people who are similar, because they're not both blind in the same places.
A partner who slows you down is only a problem if you've decided speed is the goal. Frequently the friction people report is not a defect in the match. It's the point of it.
What actually predicts difficulty is usually not the signs
In practice, the things that strain relationships tend to be concrete. Different expectations that were never discussed. Different emotional needs neither person named. One person wanting to resolve conflict immediately while the other needs space first.
Astrology can describe these differences usefully. It doesn't create them, and it can't override the effort of two people addressing them.
Where astrology genuinely helps
Not in verdicts. In vocabulary.
When you can say "I need to talk it through now and you need an hour first" instead of "you don't care," a recurring argument loses most of its heat. Chart comparison is good at surfacing exactly that kind of difference, particularly around the Moon, which relates to emotional needs, and Venus, which relates to how affection is given and received.
One thing worth saying plainly
No compatibility reading is a reason to stay somewhere that isn't good for you. If someone treats you badly, no chart offsets that, and a responsible astrologer will say the same.
How to use it well
If you're going to compare two charts, compare the full ones, which means you need both birth times. Read it as a map of differences rather than a verdict, and pay attention to what you recognise rather than what you have to force.
An astrologer on My Astrology Advisor can look at both charts with you by live chat or voice call.