Errors/Chain errors
NoTimepoint
Check the argument values against the operation schema
No timepoint was supplied but this multisig operation is already underway, so the approval cannot be matched to it. Read the operation's when field from the Multisigs entry for the call hash and pass that height and index as maybe_timepoint.
Declared by the Multisig pallet; it classifies to the semantic code invalid_argument.
Remediation
Check the argument values against the operation schema
The same explanation is available in the terminal: btcli explain NoTimepoint.