Not able to forward calls via phone settings

[SLeong]

Hi there, I was trying to set up call forwarding via MMI codes given by Boost online chat agent and also through my mobile phone call settings. Unfortunately both will not work. 

Error message when sending MMI code **21*number*10#

Call forwarding unconditionally. for All Teleservices Connection problem or invalid MMI code.

Error message when sending MMI code **21*number#

Call forwarding unconditionally. for All Basic Services Connection problem or invalid MMI code.

Error message from Samsung S8. Call Settings>More Settings:

Failed to read data Something went wrong. Check your SIM card or network connection, then try again. 

I have topped up with $5 Bolt On credit as well. But seems nothing works. Can someone please help? Thanks. 

Regards,

Sean

[bigb1]

Same problem with galaxy s7. Unable to activate call waiting. MMI code invalid.

[bigb1]

Tried all the methods mentioned on google but nothing worked. Removed sim from galaxy s7 and put that in HTC U11, activated call waiting and then again put sim back in s7. Wow call waiting is working now.

[seriously]

Factory RESET Galaxy S7 buddy