Hello,
It looks like you are maintaining two proxy destinations. Go to tcode SM59 in ECC and check the following destinations:
Type G:
SAP_PROXY_ESR (forgot the full name but it looks something like that)
Type H:
your rfc destination pointing to PI
After checking it, go to sxmb_adm->Integration Engine Configuration and see what is the entry under Corresponding Integration Server (dest://yourrfcdestination).
If it is the type H that is in the entry, you need to delete the type G. Only one should exist between the two.
Hope this helps,
Mark