Credit score is only one part of the approval. Debt obligations reported on credit, recent activity and a lot could factor in. Sounds like CCAP is tightening on their approvals.
The OP could potentially bring in their partner as a cosigner to get the deal through.
As an additional data point, I got Tier 1 when my score was significantly lower but with a higher income. I didn’t expect to get Tier 1 at that time but CCAP did not bat an eye.
Credit approvals are not plain simple as just a score.