Someone is having a problem submitting one of my forms

She said she has an older PC but she also tried it on her mobile device and said it didn't work. I know the form works because others have used it without any problems. Just wondering if all jotform forms are fully compatible with mobile devices? Specifically she is saying she couldn't get it to scroll down and when she was selecting answers, it wasn't selecting the correct answer.

Do you know what device the user is using? Android or iOS? I noticed with your form is that it's loading a bit slow even on my desktop. There's a slight delay when selecting an option.

You can see in my screencast below that there's a slight delay when using Chrome.

Kindly ask the user if using other device or using Firefox as his/her browser helps?

I will ask her.