Hi again. Thank you for your patience.
Since your former employer took the computer and phone, I assume your former employer owns both devices. Please correct me if I'm wrong.
If your former employer owns both devices, then it had the right to take back both devices. If you are asking why the former employer will not give you back the contents, I can only speculate. However, in most cases an employer has a strong argument that it owns the contents on such devices. The argument can be rebutted with evidence that the employer allowed employees to use such devices for personal reasons.
If you were to pursue legal action, then it is possible based on what I wrote above that you could win the right to remove the personal contents from the devices. But, you may have an uphill battle. I think it would be the exception rather than the rule if you were to win.
If you intend to take legal action, then I strongly suggest that you retain a local attorney. Your chances of success in the lawsuit are greatly diminished if you proceed on your own.
Does that answer your question? Please let me know if you need clarification, as I am happy to continue helping you until you are satisfied. Also,please remember to provide a positive rating via the stars(and note that your positive rating is the only way that I'll get credit for helping you, so it is much appreciated!). Thank you. :)