Jio — internet speed issues

Address:	"Paanchajanya", Near Koppada Guttu House, Padukodi, Kulur, Dakshina Kannada, Karnataka, 575013
Website:	www.jio.com

My speed was fine until yesterday, around 5 to 15 mbps. Then today my net speed came down to 80kbps when I still had 700 mb data left on my number.
Number : [protected]
I contacted support and they told me whats causing this issue is that many users are using internet at same time.
What kind of reason is that?
Please fix this.