Frequently Asked Questions
Have questions about UNDO? We got you covered! Explore the frequently asked questions by our community

How do I become an UNDO customer?
How can I transfer my actual phone number from another operator to UNDO?
Which network does UNDO use?
How many SIM cards can I order?
How to buy an eSIM?
Why choose an eSIM?
How to activate an eSIM?
My eSIM is not working
Transferring my eSIM to another phone
How do I replace a normal SIM card with an eSIM? (SIM SWAP)
How do I replace an eSIM with a normal SIM card? (SIM SWAP)
My PIN code is blocked. Where can I find my PUK code?
How can I change my PIN code?
Can I switch off my PIN code?
How can I change the language of my SIM card?
How can I find my SIM card number?
What is an IMEI number?
Where can I find the IMEI number?
My phone has been stolen/My SIM card lost
What type of format of SIM card do I need?
What is an out of bundle limit?
How do I change the out of bundle limit?
Useful numbers (1987 + 1989)
How can I activate my Voicemail?
Voicemail deactivation or reactivation
Listen to your voicemail
How to change the language of my voicemail?
How do I change the pick-up speed of my Voicemail?
How do I forward my call to another number?
How are call forwardings being charged?
I'm getting undesired malicious calls
I can't configure a personal hotspot
How much characters an SMS can it contain?
I can't send SMS messages
Does UNDO has a 5G network?
Does UNDO support VoLTE & VoWIFI?
How can I stop third party services?
How do I suspend my number temporarily?
How can I stop my subscription/contract?
How can I delete my account?
What is the difference between "International" and "Roaming" calls?
Calling from abroad (Roaming)
I cannot call, send an SMS or surf abroad
Calling to abroad (International)
When does my invoice start?
How do I receive my invoices?
What happens if I don't pay or forget to pay?
How can I pay my invoices?
What are my CO² emissions?
What are my CO² compensations?
How are my emissions calculated?
What are my carbon KGs?
What is UNDO Removal?
What is UNDO Forest?
What are UNDO Forest add ons?
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