By Depending on your FreePBX version, by default, SIP Station trunks are may be created as Chan SIP, you can use this wiki if you have already installed the SIP Station Key in your PBX or if you are looking forward to configuring a new SIP Station service.
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After you click in Remove key, you will see this screen to add the account key again. Please apply config to continue.
Step 2: Enabling the Experimental SIPStation PJSIP Mode
Go to Settings-> Advanced settings-> SIPStation Module-> Enable Experimental SIPStation PJSIP Mode . Enable the option clicking in the Yes button, then click in submit and apply config.
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