If you're on android, going to google maps, then back to POGO can help the app find the correct location. if Gmaps is also drifting, enabling/disabling wifi or wifi sharing can help. In addition, there are apps that can be used to manually re-download AGPS data, which helps sometimes. If all else fails, rebooting your phone can be tried as a last resort.
Frequency of raids during events...
I have a total of ten gyms that are visible from my home and throughout the whole day I only saw two lvl. five raids. Since it's during a raid exclusive event shouldn't the frequency be higher? There also seem to be downtimes during the 24 hr day when barely any or no raids spawn (during the day when everyone's at work and at night respectively). Shouldn't they get rid of this during raid exclusive events?
(Context: I'm salty because I wanted my first Ho-oh and none spawned in walking distance, and I couldn't use my last free raid pass in a 3rd raid because the game decided to put me in the middle of lake and didn't budge.)
Answers
I use one called "GPS status", it does the re-download just by opening it. So I open GPS status, wait a few seconds for it to download, then open google maps, then open Pogo. It works often for me and I have to use it quite frequently because my GPS chip is horrible and drifts a lot even when outside.
Sounds like bad RNG in your area.
My area had about 30 organized Legendary Raids on Saturday alone. Which may sound like I'm bragging or mocking you, but really, I've got 100 Lugia candies, and 80 Ho-Oh candies, I've got 15 of each or so in my Inventory right now (because I can't transfer Legendaries because I'm dumb that way), and I never use them now. I powered up a Lugia back when they first came out, so that I could solo Machamps, but I've got 4 Level 40 Attack 15 Machamps (and 1200 Candies) right now so I don't Solo Machamps anymore. Beyond that, they're not useful Pokémon at all for me. So this weekend? A nice break from Legendary Raiding, ironically. (Oh, I did a few - but mostly to help newbies reach the 6 Trainers needed for a Lugia or Ho-Oh, or to help my wife and daughter get through the Meltan Quest)
Speaking of Meltan, my daughter is stuck on the "Catch a Cubone" part of the Meltan quest and we were really, REALLY hoping for an Alolan Marowak to spawn to finish that part of the quests. That was the only raid were were looking to do, so we were waiting for one to spawn.
Which it didn't. Either day. Sigh.
So actually, I sympathize with your lack of the raids you wanted to do and I wish that the raids were more equal. Not 30 Legendary's and 0 Marowak's - that's the RNG that I prefer to called "R"NG, but I used that so much that people got annoyed with it. (I still think leaving the quotation marks out is an insult to the word Random, but I think Random understands that I'm not being insulting towards it.)