Make these collections calls stop! Give us a call at 1-855-697-3825 or send us an email at email@example.com and we can have those calls stopped for you. Related articles I keep receiving calls from SIMM. Who are they? What is my credit limit, and how do I increase or decrease it? When will I be sent to collections? How does AutoPay work and where do I set it up? Why aren't my new purchases showing up in my Current Balance?