As you describe it, I don’t think is is a conflict of interest, but it does seem a bit strange. Yes, the Secretary and Treasurer can write a check if they are signatories. If your Association is professionally managed, they should be discussing with you about having TWO signers/approvals for each check, that way, no individual can write a check.
If you are self-managed, you may want to engage the bank you are using to require two signatures per check when presented for payment. Without two signatures, the check can’t be cashed/processed.
Hope that helps!
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