Compose Apologetic Payment Reply

I recently missed a deposit to Shelby because my account balance was too low, and I need a concise, friendly, and apologetic message that explains the situation without sounding dismissive. The note should:

• Open with a sincere apology
• Briefly mention the insufficient balance as the reason the transfer failed
• Reassure Shelby that nothing else has changed on my end
• Ask her to try the deposit again later, and thank her for her patience

Please keep the tone warm yet professional, no longer than a short paragraph, and supply the final text in a simple document I can copy-paste into email or chat.