2146700 - INSERT LOCATION error "The maximum number of connections have already been opened" - SAP IQ

insert .. location '' { select .. } job in IQ fails with following error

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I. Exception Thrown from hqm_con.cxx:192, Err# 1, tid 107 origtid 107
I. O/S Err#: 0, ErrID: 8192 (hqm_exception); SQLCode: -1003002, SQLState: 'QHA02', Severity: 14
I. [20174]: CtLibrary Error: 6, Severity: 0, Origin: 1, Layer: 1
Error Message: ct_connect(): user api layer: external error: The maximum number of connections have already been opened.
OS Error: 0, OS Message: .
-- (hqm_con.cxx 192)
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location is another IQ server which has -gm 200 ( 200 maximum connections ) but sp_iqconnection shows enough available connections.

Why "maximum number of connections have already been opened" message even though more connections can be made to server identified by location ?

SAP IQ 15.x
SAP IQ 16.x

KBA , BC-SYB-IQ , Sybase IQ , Problem