The following shows how to change the current value of a sequence for a specific tenant:

define variable sequence as ISequence no-undo.
define variable sequence as ITenant no-undo.

assign
  sequence = service:GetSequence("OrderSeq")
  tenant   = service:GetTenant("ACME")
  sequence:SequenceValues:Get(tenant):CurrentValue = 2001. 

service:UpdateSequence(sequence).