whois-db variations / authentication info

Good morning,

we became an Autonomous System and now we're trying to update some
informations on our whois records without success.

Modify FAILED: [person] GVAG1-RIPE Gabriele V. A. Gianolli
***Error: Authorisation failed
***Info: Syntax check passed

.......


  ***Info: Authorisation for [person] GVAG1-RIPE

using mnt-by:
not authenticated by: AS1836-MNT, CH-ZZ-MNT

it seems that we need to be authenticated by our two previous mantainer.
If there is need to insert a password for these objects, then there is a
problem:
      we don't know these passwords!

How could we solve this problem?

Thanks in advance.

Christian Bertoldi
ABN-AMRO Bank Switzerland
+41 091 695 4955
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