Did you change your Lightning address from walker@getalby.com to something different?

If not you should message nostr:npub1q5sah9f3p9kl7uqdeaqskqwmg74ktxx70e0093dzh4lpzcp3t0mqzxky65 or nostr:npub1xv8mzscll8vvy5rsdw7dcqtd2j268a6yupr6gzqh86f2ulhy9kkqmclk3x for support. I just tested sending the same amount to your Alby address and  mine from Primal and got an error with only yours.
https://image.nostr.build/a625eddf0d8f3543bfab4dcb6b95611ae1cea791370f8407a840410a78fd2812.jpg
https://image.nostr.build/f3b474e2f609625958979273c9d6c45a185d8d525eda6ca30edad0cb4a1cc27d.jpg