Issue updating rack from convox version 20191001204055 to 20191001204055: Certificate not found

The certificate pointed by arn was for the domain *.convo-route-.us-east-1.convox.site.
It was expired so we deleted it and hoped that on a retry of convox rack update it would get re-created. But we still get the following error:
2019-10-07T23:58:58Z system/aws/cfm convox UPDATE_FAILED RouterListener443 Certificate ‘arn:aws:acm:us-east-1:<acct#>:certificate/<cert#>’ not found (Service: AmazonElasticLoadBalancingV2; Status Code: 400; Error Code: CertificateNotFound; Request ID: aea1627d-f1f4-4729-89c0-096cb363f13b)
We are unsure as to why the cert arn has not been updated even after the cert had been deleted. Any help with getting this issue fixed would be appreciated!