Wrong CID when performing a "semi-attended" transfer

When i do a "semi-attended" transfer which is first to transfer a call like a attended but then press the transfer button again to send it like a blind transfer. This is working fine but if i blind transfer it while the other extension is still ringing from the attended transfer the CID show my extension instead of the remote party that call me in the first place.

Exemple :

1- I get a call for 45298xxxx on my extension 20 and that guy want to talk to the extension 21

2- I transfer it to extension 21 on which it does using an attended transfer

3 - But i just want to send it the call i don't want to speak to the guy first so i press the transfer button again to send it like a blind transfer while it stil ringing

4- but instead of having the number of the remote party that first call me (45298xxxx ) the CID show my extension number (20) even tho i have blind transfert it. and this may cause issue because the guy at th extension 21 think it me that call him instead of a client.

If i only do a blind transfer or an attended transfer and the guy anwser before i send him the call now the CID show the number of the remote party that first call me

The phone that i'am currently working with are grandstream GXP-2130 and 2160

Thank You