*Phone number*

Hi good morning!!
I hope someone can help me with the problem I’m having, I installed the “joinchat” plugin and when I’m configuring it in the field where the “contact phone” goes, it doesn’t accept my number? and on the side I see a button that says “test number” but it appears disabled and I can’t press it? and when saving the changes it does not save the number? And without that number, the WhatsApp bubble cannot appear on my website. Anyone who can help me would appreciate it a lot!
I await your response, thank you!