The reason for this decision was sanctions from the European Union.

In Bulgaria , a transfer in the amount of 890 thousand dollars to the Russian embassy was blocked.
It is reported by BNR .
The reason for this decision was sanctions from the European Union.
“There is a transfer to the Russian embassy, which falls directly under the sanctions of the European Commission. The Russian embassy called for the lifting of sanctions for this transfer, and now the cancellation is being agreed with the EC,” said Bulgarian Finance Minister Asen Vasilev.
After clarifications from the European Commission, the Bulgarian authorities will decide what to do with the funds.
Earlier, Finland arrested almost a thousand freight wagons belonging to Russian companies due to European Union sanctions.
The Russian Embassy in the Bulgarian capital Sofia has stopped issuing tourist visas for Bulgarian citizens.
(C)UNIAN 2022

Looks like the bribe money won’t be given out anytime soon.
Good job, Bulgaria!