Clipboard text can include spaces, line breaks or typographic characters that were not intended as part of a login. Compare the values carefully and remove only accidental formatting. Do not change the actual password merely because it contains unfamiliar punctuation.
Paste one field at a time
Copy the username separately from its label and paste it into a plain field. A message reading Username: followed by a value does not mean the label belongs in the login box. Long-press selection on a phone can easily pick up the following line as well.
Watch the beginning and end
An invisible trailing space is difficult to notice on a television. Move the cursor to the end and compare the number of visible characters with your account note. Avoid password-reveal controls when other people or a recording camera can see the screen.
Keep case and punctuation intact
Usernames and passwords may be case-sensitive. Similar-looking characters such as a capital I, lowercase l and numeral 1 deserve particular care. If a password manager can store the account securely, save the original value there rather than repeatedly transcribing it from a screenshot.
