Did you try to follow a factory reset procedure you can find in user the user manual for this
Ericsson satellite phone:
Phone Lock (PIN)
The phone lock protects the phone against unauthorized use of the phone if there is a theft. The phone lock is not activated when you buy the phone. Upon purchase the phone Personal Identification Number (PIN) will be set to 0000. If the phone PIN is enabled, when you switch on the phone, the message
‘Phone PIN Enabled’ will be displayed. It is strongly recommended that you enable the Phone PIN. If you do not like the original number we recommend that you change it to one you find easy to remember.
Enter your PIN carefully

If you enter the PIN incorrectly, you will be notified of this and asked to re-enter it. If you enter your PIN incorrectly three times in succession, the
SIM card will be blocked and the
phone will be disabled for all foreign SIMs and the message
‘Phone Disabled’ will be shown on the display

If this happens you can unlock it by using a Personal Unblocking Key (PUK) code. Contact your operator to obtain this code. See “Unblocking with Personal Unblocking Key (PUK)” below.
The phone PIN can ONLY be changed when the MASTER SIM is inserted, (the SIM fitted when the phone PIN was first enabled). If a different SIM is used, the message ‘Request Rejected’ will be given.Unblocking with Personal Unblocking Key (PUK):When you buy your SIM Card, you obtain a 4- to 8- digit Personal Identification Number (PIN) and a Personal Unblocking Key (PUK). The PIN is the code that you enter to get access to and activate your subscription. PIN 2 is used with special functions, such as price. The
PUK (and PUK 2)
is a code that helps you unlock your phone when you have forgotten the PIN (PIN 2). If you have entered the PIN incorrectly three times in a row enter the following from stand-by:
<* <* 0 5 <* SIM PIN1 Unblocking Key
Then enter the new number.
<* New SIM PIN1
Enter the new number again to confirm.
<* New SIM PIN1 #> 
It is important to know that new PUK code given to you by your provider or Erricsson will be rejected if the
MASTER SIM is not present in
R290 handset.
It is the phone that is locked, not the card (the same SIM should work fine in other handsets), and to be unlocked you need to go through PUK unblocking procedure using
the same SIM card that was in the phone when device was disabled. The phone, generally speaking, should work and it should have a signal and satellite service. You should be able even to make 000 calls. It is just that device has been locked due to three wrong PIN entries.
Not having a master SIM (the SIM you first put in phone), means you have to get the phone reset by somebody who has the right software and knowledge how to do it. I know facilities in USA, Canada and UK (cost £10 - £15) which can clear it by doing a master reset of R290 satellite phone, but the shipping costs from your location could be prohibitive factor in this case.