router bgp 203725 specifies your local AS-number, not the peer AS-number. A router can be part of only one ASN.
It seems that you're just making a typo though: 203725 and 203735 are two different numbers. So you can configure more peers by starting with router bgp 203735 (unless your entire BGP config is wrong, and your ASN is actually 203725).
There is no actual factory reset like there is on a consumer-grade router. You must perform a password recovery, then you can erase the startup configuration and reload.
See the detailed instruction in the link above to get into enable mode, then you can:
Do not save the running configuration when prompted.
I don't have the rep points to comment above but, what Ron Maupin said about the explicit deny being pointless is wrong. With only the implicit deny, you will only see denied traffic if your logging level is set to Debugging or you're using "terminal monitor". If your logging level is anything lower than Debugging (such as Error) you will not see the ...