First, clarify with the bank exactly what's been blocked - just the card or the entire account. This is key because if only the card is blocked, the account stays active and your money is accessible. Call Sberbank's hotline, explain the situation, and ask either for the card to be unblocked or for help withdrawing cash. The bank can usually transfer money to another card of yours (if you have one at a different bank), issue a check, or just give you cash at a branch when you show your passport.
If you need money urgently, don't wait for the card to be unblocked - go straight to a teller at a branch and ask them to withdraw cash from your account. You'll need to come in person with your passport, and it's usually done quickly. Some banks let you withdraw at the counter even without a card, as long as the account is active.
But here's what people often miss: when a card gets blocked due to suspicious activity, the bank might freeze the entire account while they investigate. Check this right away when you call - if the account is also frozen, there's nothing you can do without getting it unblocked, and at that point you just have to be patient and work with the bank.