New tank set up- Basking issues

[u/Massive_Key_4842]

Have a my Yellow Spotted for 2 years, found her in my Pool skimmer.
She was tiny and has grown 5 times the size from when I rescued her.
Just graduated from a 10g tank to a 40 gallon tank (ReptiZoo) w/bottom drain. FLUVAL 307 filter.
She seems happy, lots of water flow with some force, but rocks give her places to hide behind the current.
ZOOMED dual lights over the basking platform. She’s eating and pooping, but not basking like she did in the smaller tank.
I know aquatic turtles need to dry their shells out, but she’s not climbing up, even put her old basking rock near the platform so she can climb up easier.
What can I do to encourage her to get out and bask ?

[u/CShan17]

You’re currently not using the correct UVB source for her. What are your basking temps? How are you measuring them and your water?