Don't know about the phone part, because I don't use my phone for this.
I can provide some help for the daily searches on your computer though. I've had the same issue for about a week now. I'd do 30 research, and it would only give me 3 points ( as if I had only done 1 search ) everytime. I've found a way to avoid this bug.
When you're on your rewards.bing.com page, click on your " points breakdown " . Then click on the PC/computer searches link, it'll open a new tab.
Type anything you want in the search bar, but before you hit enter, select all of what you just typed, copy it, and then press enter to do your research. Then close the current tab.
It'll bring you back to the previous tab, where 3 points should be credited. Click on the PC/computer searches link again, which will open a new tab again, paste your previous search and just add one random letter at the end to register it as being a new search, then select all and copy, then press enter to do the research, then close the tab again, 3 more points should now be credited ( should have 6 points ) .
Repeat the process again and again until you reach the daily max limit.
VERY much time consuming indeed, yes. But at least it works, which is better than nothing.
Edit:
Microsoft are clearly trying to put an end to the rewards program. I mean, first, they removed the Edge bonus. Then, they created this bug for PC searches to mess with people so that people stops doing it because way too much time consuming to do it like that. And today they lowered the amount of points earned once again, as most of the 5 points stuff has now be lowered to only 1 point today.
I won't click on those anymore, as this is cleary a waste of time considering they don't give anything in return anymore. I'll only click the stuff that gives at least 30 points from now on, and ignore the rest. Only 1 point for the time it takes is clearly an insult to people's time and is not worth it.
Besides, they're also doing this, so...
https://www.gamingdeputy.com/bad-news-the-microsoft-rewards-application-will-disappear-on-xbox-xbox-one/
That's right, the daily bonus is about to go away too... We're getting as close as possible to 0 points a day, so, yeah, the message is clear, they're slowly stopping the program without stating it officially.
My best advice would be: If you have any points left, use as many of them as you can before it's too late. Because, I have a feeling that one of these days, the program will be closed without any warning before hand, and every remaining points will be lost forever. So, my advice would be to keep that amount of points as low as you can.