Currently there is no way to remove the entire imported file. However, if you click on the pencil icon (from the crypto summary), you can choose which transactions you want to include as taxable. You can either check them all off and remove the ones that don't belong - or can can clear them all and check off the ones you want to keep.
You can also edit the individual transactions and zero out the one you don't want to include. Everything you import will remain on the return, but TurboTax will only include the transactions you mark as taxable. And as a last resort, you can clear and start over. This will clear out everything from your return. If you have just started your return, this may be a better option.
To see all of your imported transactions, click on Add More Sales and then click on See my uploaded transactions. From there you can choose the transactions you want to keep or discard. Only the ones you mark as taxable will be transferred to your tax return.
Is it so hard for TurboTax to put a DELETE button next to or near to the SELECT button.?
Pretty poor software design. Or just lazy ?