Annual budget almost exhausted for &1

What causes this issue?

The current budget consumption is &V2& less than the annual budget for
the FM account assignment &V1&. Depending on the type of document, this
FM account assignment is either a budget address, posting address, or
RIB object/RIB source address representing an RIB rule with call
procedure.
Budget control on outgoing amounts (
<DS:DE.BUAVC_CEILTYPE>ceiling type</> <ZK>Expenditures</>) raised this
message for the following combination of availability control ledger,
fiscal year (and if applicable, <DS:DE.FM_CEFFYEAR_BCS>year of cash
effectivity</>) and control object:
<ZH>&V3&</><ZH>&V4&</>
DEFINE &N& = '003'
INCLUDE FMAVC_ANNUAL_MESSAGE_EXT

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.