Suggested fix (unconfirmed): Open your inventory during the massage session to toggle off the timer.
The problem
After getting Sana to max level, the game informed me that I was able to buy the limitless timer item or whatever in the shop. However, I don't know how to toggle off the timer. Any help?
Suggested fix (unconfirmed): Navigate to C:\Users\User\AppData\Local\Massage\Saved to find and transfer your save files. Ensure you copy the save data into this exact directory on your main PC.
Suggested fix (unconfirmed): Purchase the required self-massage skill first. Alternatively, hold down the left mouse button while placing your hand on the character, then press the middle mouse button.