Do not play strictly to a metronome. Most professional scores, such as the Robert Lunn arrangement , specify playing "freely throughout" (rubato) to allow the melody to breathe. Recommended Tab Sources for Further Study
If you are using tabs based on Jeff Beck’s version, the "fix" is often in the performance technique rather than just the notes: Floating Tempo nessun dorma guitar tab fix
| Beat | String | Fret | Finger | Note | | :--- | :--- | :--- | :--- | :--- | | 1 | E (High) | 8 | 3 | C | | 1 | B | 7 | 2 | F# | | 1 | E (Low) | 0 | - | E | Do not play strictly to a metronome