https://www.amazon.com/Spigen-Charger-Charge-Adapter-MacBook/dp/B0BD462WV7/ This is the safest one available. The 30w port will charge about 6 minutes slower than the 45w. More on reddit.com

Does it charge with Samsung's original charger? If not then check if the charging port is dirty, might need cleaning. Also check 2 diffrent cables. More on reddit.com

Since about Jan or Feb 2021 an update was released to most / all Galaxy flagships at the time and one of the ninja changes was to prevent Galaxy devices from fast charging (10w - 15w) by non-authentic / third party wireless FAST CHARGERS. You will only be able to normal wireless charge at 5w - 7.5w (both are regular wireless charging) on these third party fast wireless chargers. Ever since then only Samsung official / authentic wireless fast chargers will let you fast charge Galaxy devices, which could explain why it works in power save mode since that prevention routine might be turned off in that mode. However, Samsung has never made an official announcement or blogpost acknowledging any of it afaik. Your only option is a wired fast charging solution unless Samsung offers a wireless fast charger specifically for windshields / dashboards. More on reddit.com

Fast charging doesn't degrade your battery... that's a common misconception.

Cnet wrote an article about it a few weeks ago...

6 battery life truths about Galaxy S20, iPhone 11 and other top phones

Fast-charging won't damage your battery

A conventional charger has an output of 5 to 10 watts. A faster charger can improve that by up to eight times. For example, the iPhone 11 Pro and Pro Max come with an 18-watt fast charger, the Galaxy Note 10 and Note 10 Plus have 25-watt chargers in their boxes. Samsung will sell you an extra-speedy 45-watt charger for $50.

Unless there's some technical flaw with your battery or charger electronics, however, using a fast charger won't do your phone's battery any long-term damage.

Here's why. Fast-charging batteries work in two phases. The first phase applies a blast of voltage to the empty or nearly empty battery. This gives you that blazing charge of from 50 to 70% in the first 10, 15 or 30 minutes. That's because during the first phase of charging, batteries can absorb a charge quickly without major negative effects on their long-term health.

For instance, Samsung promises its 45-watt charger can go from zero to a 70% charge in half an hour. Apple says the fast charger that comes with its iPhone 11 Pro can hit a 50% charge in 30 minutes.

You know how it seems to take as long to fill up that last 20 or 30% of the battery as it does to charge the first 70 or 80%? That last part is the second charging phase, where phone-makers have to slow down and carefully manage the charging speed or else the charge process actually could damage the battery.

Arthur Shi, a tear-down engineer at the DIY repair site iFixit, suggests to imagine a battery as a sponge. When you first pour water onto a dry sponge, it absorbs liquid quickly. For a battery, this is the fast-charging phase.

As you continue to pour water onto the increasingly wet sponge at the same rate, the liquid will bead up on the surface as it fights to soak into the saturated sponge. For a battery, this unabsorbed charge can result in shorts and other issues that could potentially damage the battery.

Damage is rare if everything's well-managed inside. A battery's management system closely monitors the two charge phases and drops the charging speed during the second phase to give the battery time to absorb the charge and avoid issues, which is why it can take 10 minutes to get those last few percentage points.

The case of the Samsung Galaxy Note 7's tragically exploding battery resulted from battery design flaws rather than from the phone software's battery management techniques.

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