User cannot be contacted - this will not affect your response rate.

[jackmchale]

I have this customer that has placed multiple orders with me before and all has gone smoothly. Then out of nowhere, today it shows the “can no longer be contacted” message that is usually shown for spammers. He was a genuine person, very cooperative and was a repeat customer, so I don’t see why they’ve blocked his account. Is there any reason for this other than spam?

[infinite_flyers]

Sometimes the are spam massages come to sellers, but the fake account is bang from Fiverr itself. it didn't affected to your gig or impresssions.

[theratypist]

16 hours ago, jackmchale said:

Is there any reason for this other than spam?

Other than Fiverr disabling their account, it could also be they deleted their account on their own terms.