Two of my sites are having this issue. Authorize.net support is saying it's a Magento problem. I haven't patched or changed any code this week. Anyone out there seeing this in the wild?
UPDATE 1
A users on the M1 support forum posted a temporary fix. I applied the change and it worked.
UPDATE 2
My host hinted that Authorize.net reverted the change. I substituted the multiple char delimiter and it is back to working as normal. Authorize.net's response has been atrocious, I'm going to be digging into bolt's checkout.
