Don't give up just yet, you still have a chance, you might be able to convince Slush to just send you the rewards to the old address, Artemis3 is a team member at BO and a good forum member so he should be first to reach out to.
The second person would be Irina the head of support, Jan Čapek is also a very helpful person (I think he is the founder or something), anyway, you can find all these folks on telegram
https://t.me/BraiinsOS, you might want to PM them instead since that channel is more about the firmware than the mining pool itself, you don't want to be spamming the wrong group.
Again, don't feel bad, chances are, you are going to get your money back, keep us updated.
Indeed, this type of case and any other
Slush Pool issues are handled via
support ticket at the
Slush Pool site itself.
The Telegram concept for what is a
Group vs
Channel is different, with the later originally not allowing chat but now its an optional feature to allow discussion in a separate tab.
The
channel called Braiins is for the company announcements. It has
discussion enabled, but its not (really) meant for support.
The
groups called
Braiins OS (
EN ES RU FA ZH) are, for
Braiins OS which is the ASIC mining firmware
There is a also a
channel that notifies when each block found in Slush Pool.
Any other groups/channels in Telegram bearing the name "Slushpool" or any variant of, are scammers.