Contact their customer support team to change your Bitcoin withdrawal limit on the Cash App:

• You can do this by opening the app and selecting the profile icon in the upper-left corner. 
• From there, scroll down and select “Cash Support,” then select “Something Else,” and finally, “Bitcoin.”
•  Here, you can describe your issue and request to change your withdrawal limit.

Cash App may require additional information or documentation from you to verify your identity before changing your Cash App bitcoin withdrawal limit. Once your identity is verified, Cash App will review your request and let you know if they can increase your limit. If your request is approved, your new withdrawal limit will be applied to your account.