Need help with this issue

First of all, I apologize I'm new to networking. also, I couldn't post the network diagram and I don't know if this is the right place to post this issue.

Basically, we have 2 PCs connected to 2 different networks and I configured the static route between the 3 routers and it works fine. as shown below

PC1-->SW1<-->R1<-->R2<-->R3<-->SW2<-PC2

• the issue is from PC1 I can ping and reach the interface of R3 but I cant reach PC2 and going back from R3 I can ping PC1.
• Basically cant reach PC2 and SW2

To More points to highlight:-

1. SW2 can only Ping R3
2. SW2 is configured exactly as SW1 beside the IP and gateway.

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Thanks