Unable to edit ‘Custom Message’ whne sharing Post

Hi all,

I am unable to edit or remove the ‘Custom Message’ in the ‘sharing posts panel’. Every post that is now shared to my soc meds has the same title. I have no access to edit it in wordpress because it is greyed out.

I have tried to remove it in the orignal post but it is greyed out there too.

See SS for more details >https://imgur.com/a/oSxrNBq

Any suggestions as to how to remove it will be appreciated, thanks.

Regards,