If you find that the MyIQ games are too repetitive, try using them as warm-ups and then switching to other brain-training games, memory exercises, or logic problems that use the same skills in different ways.
This variety keeps your brain from getting stuck in automatic reactions, which can stop your progress.
Keep track of your scores over time and give yourself small goals for each session, like increasing your speed of reaction or accuracy by a small percentage. This way, you'll be pushing yourself on purpose.
If the platform lets you, make the games harder or switch to types of games you don't normally play to keep your brain active and keep your skills from getting stale.
Many people have shared their issues here and found resolutions. If you have one, feel free to reach out to Xolvie.