(This message post is not indended as a direct reply to anyone. Just posting for general knowledge feedback to the community)
A faster speed is not the compatibility issue. Rather it is the technology standard being used or file format or other problem (continue for details). Some cheap cards are sometimes not properly labeled or there are other quality control manufacturing issues.
There are are 4 technology standards for SD cards
SD (also called SDSC) - up to 2 GB
SDHC - up to 32 GB
SDXC - up to 2 TB
SDUC - up to 128 TB
SDHC and SDXC are currently the most popular. The original SD (now also called SDSC) standard is pretty much antiquated now but may still be needed for older devices. SDUC was just introduced this year and I haven't seen anything use it yet.
You can see these and their logos here:
https://www.sdcard.org/developers/overview/capacity/If you have a properly sized and correct technology type card and it doesn't work the other compatibility issue could be the file system formating used (FAT16, FAT32, NTFS, exFAT... etc.). So try reformatting the card using the supported format for the device. Lots of devices also prefer to do their own formating rather than another computer doing it, as some use non-standard formats often with accompanying files or hidden partions.
A card that is good reputable brand, properly type matched, formated with the supported file system, should work on any device requiring that standard regardless of it being a fast speed. Sometimes even after matching technology standard type and file format the problem is that the card is not fast enough (usually lock up or freezing or errors results). A faster card always helps and never hurts. Cards go bad too which is something to keep in mind. An identical card may work where one might have thought it wasn't compatible before trying a second identical card.
Usually a faster card does use a different technology standard. Two cards that are from the same manufacturer and the only thing that appears different is the storage size could really also have differences in technology standards. There are also a lot fake cards on the market. They have been hacked to report a larger size when you format or insert them. These fake cards sometimes are off brand or sometimes have reputable brand names but they are truly fake. Only buy from reputable sellers. Even Amazon has bad sellers sneak in.
Another issue in compatibility is the adapter used, or reader used. Sometimes people use an adapter that is not compatible or doesn't make good contact with a specific worn card. Sometimes people use a reader (USB adapter or like device) to access the card and the compatibility issue is that the adapter or reader is of older supporting technology.
