Can I block myself from swap requests?

Yes. Open Settings and under Privacy, turn off the Allow Swap Requests option.

Then you won’t appear in others’ searches and won’t receive new requests. Existing requests and chats will remain. You can turn the option back on at any time.

You can decline individual requests by tapping Decline. This is final; the same tour cannot be offered to you again afterwards. The person who requested won’t know it was you.